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as one of the most notorious gangsters in history , al capone presided over a vast and profitable empire of organized crime . when he was finally put on trial , the most he could be convicted of was tax evasion . the nearly $ 100 million a year , that 's 1.4 billion in today 's currency , that capone had earned from illegal gambling , bootlegging , brothels , and extortion , would have served as evidence of his crimes . but the money was nowhere to be found . capone and his associates had hidden it through investments in various businesses whose ultimate ownership could n't be proven , like cash-only laundromats . in fact , those laundromats are part of the reason for the name of this activity , money laundering . money laundering came to be the term for any process that cleans illegally obtained funds of their dirty criminal origins , allowing them to be used within the legal economy . but capone was n't the first to launder money . in fact , this practice is about as old as money itself . merchants hid their riches from tax collecters , and pirates sought to sell their bounty without drawing attention to how they got it . with the recent arrival of virtual currencies , offshore banking , the darknet , and global markets , schemes have become much more complex . although modern money laundering methods vary greatly , most share three basic steps : placement , layering , and integration . placement is where illegally obtained money is converted into assets that seem legitimate . that 's often done by depositing funds into a bank account registered to an anonymous corporation or a professional middleman . this step is where criminals are often most vulnerable to detection since they introduce massive wealth into the financial system seemingly out of nowhere . the second step , layering , involves using multiple transactions to further distance the funds from their origin . this can take the form of transfers between multiple accounts , or the purchase of tradable property , like expensive cars , artwork , and real estate . casinos , where large sums of money change hands every second , are also popular venues for layering . a money launderer may have their gambling balance made available at a casino chain 's locations in other countries , or work with employees to rig games . the last step , integration , allows clean money to re-enter the mainstream economy and to benefit the original criminal . they might invest it into a legal business claiming payment by producing fake invoices , or even start a bogus charity , placing themselves on the board of directors with an exorbitant salary . money laundering itself was n't officially recognized as a federal crime in the united states until 1986 . before that point , the government needed to prosecute a related crime , like tax evasion . from 1986 on , they could confiscate wealth simply by demonstrating that concealment had occurred , which had a positive effect on prosecuting major criminal operations , like drug traffickers . however , a legal shift has raised concerns involving privacy and government surveillance . today , the united nations , national governments , and various nonprofits fight against money laundering , yet the practice continues to play a major role in global crime . and the most high-profile instances of money laundering have involved not just private individuals , but major financial institutions and government officials . no one knows for sure the total amount of money that 's laundered on a yearly basis , but some organizations estimate it to be in the hundreds of billions of dollars .	with the recent arrival of virtual currencies , offshore banking , the darknet , and global markets , schemes have become much more complex . although modern money laundering methods vary greatly , most share three basic steps : placement , layering , and integration . placement is where illegally obtained money is converted into assets that seem legitimate .	money laundering is a :
you probably know the feeling . your phone utters its final plaintive `` bleep '' and cuts out in the middle of your call . in that moment , you may feel more like throwing your battery across the room than singing its praises , but batteries are a triumph of science . they allow smartphones and other technologies to exist without anchoring us to an infernal tangle of power cables . yet even the best batteries will diminish daily , slowly losing capacity until they finally die . so why does this happen , and how do our batteries even store so much charge in the first place ? it all started in the 1780s with two italian scientists , luigi galvani and alessandro volta , and a frog . legend has it that as galvani was studying a frog 's leg , he brushed a metal instrument up against one of its nerves , making the leg muscles jerk . galvani called this animal electricity , believing that a type of electricity was stored in the very stuff of life . but volta disagreed , arguing that it was the metal itself that made the leg twitch . the debate was eventually settled with volta 's groundbreaking experiment . he tested his idea with a stack of alternating layers of zinc and copper , separated by paper or cloth soaked in a salt water solution . what happened in volta 's cell is something chemists now call oxidation and reduction . the zinc oxidizes , which means it loses electrons , which are , in turn , gained by the ions in the water in a process called reduction , producing hydrogen gas . volta would have been shocked to learn that last bit . he thought the reaction was happening in the copper , rather than the solution . none the less , we honor volta 's discovery today by naming our standard unit of electric potential `` the volt . '' this oxidation-reduction cycle creates a flow of electrons between two substances and if you hook a lightbulb or vacuum cleaner up between the two , you 'll give it power . since the 1700s , scientists have improved on volta 's design . they 've replaced the chemical solution with dry cells filled with chemical paste , but the principle is the same . a metal oxidizes , sending electrons to do some work before they are regained by a substance being reduced . but any battery has a finite supply of metal , and once most of it has oxidized , the battery dies . so rechargeable batteries give us a temporary solution to this problem by making the oxidation-reduction process reversible . electrons can flow back in the opposite direction with the application of electricity . plugging in a charger draws the electricity from a wall outlet that drives the reaction to regenerate the metal , making more electrons available for oxidation the next time you need them . but even rechargeable batteries do n't last forever . over time , the repetition of this process causes imperfections and irregularities in the metal 's surface that prevent it from oxidizing properly . the electrons are no longer available to flow through a circuit and the battery dies . some everyday rechargeable batteries will die after only hundreds of discharge-recharge cycles , while newer , advanced batteries can survive and function for thousands . batteries of the future may be light , thin sheets that operate on the principles of quantum physics and last for hundreds of thousands of charge cycles . but until scientists find a way to take advantage of motion to recharge your cell battery , like cars do , or fit solar panels somewhere on your device , plugging your charger into the wall , rather than expending one battery to charge another is your best bet to forestall that fatal `` bleep . ''	the electrons are no longer available to flow through a circuit and the battery dies . some everyday rechargeable batteries will die after only hundreds of discharge-recharge cycles , while newer , advanced batteries can survive and function for thousands . batteries of the future may be light , thin sheets that operate on the principles of quantum physics and last for hundreds of thousands of charge cycles .	rechargeable batteries are different than standard batteries because _____ .
this image of the vitruvian man , taken from leonardo 's sketches , has become one of the most recognizable symbols of the renaissance . but why ? it 's a simple pen and ink drawing , right ? wrong ! let 's start to answer this question with a math problem . i know how to calculate the area of a circle . i take the value for pi and multiply it by the radius squared . i also know how to take the area of a square . i multiply the base by itself . but how can i take the area of a circle and create a square with an equal area ? this is a problem often called `` squaring a circle '' that was first proposed in the ancient world . and like many ideas of the ancient world , it was given new life during the renaissance . as it turns out , this problem is impossible to solve because of the nature of pi , but that 's another story . leonardo 's sketch , which is influenced by the writings of the roman architect , vitruvius , places a man firmly at the center of a circle and a square . vitruvius claimed the navel is the center of the human body and that if one takes a compass and places the fixed point on the navel , a circle can be drawn perfectly around the body . additionally , vitruvius recognized that arm span and height have a nearly perfect correspondence in the human body , thus placing the body perfectly inside a square as well . leonardo used the ideas of vitruvius to solve the problem of squaring a circle metaphorically using mankind as the area for both shapes . leonardo was n't just thinking about vitruvius , though . there was an intellectual movement in italy at the time called neoplatonism . this movement took an old concept from the 4th century developed by plato and aristotle , called `` the great chain of being . '' this belief holds that the universe has a hierarchy resembling a chain , and that chain starts at the top with god , then travels down through the angels , planets , stars , and all lifeforms before ending with demons and devils . early in this philosophic movement , it was thought that mankind 's place in this chain was exactly in the center . because humans have a mortal body accompanied by an immortal soul , we divide the universe nicely in half . around the time leonardo sketched the vitruvian man , however , a neoplatonist named pico della mirandola had a different idea . he pried mankind off the chain and claimed that humans have a unique ability to take any position they want . pico claimed that god desired a being capable of comprehending the beautiful and complicated universe he had created . this led to the creation of mankind , which he placed at the center of the universe with the ability to take whatever form he pleases . mankind , according to pico , could crawl down the chain and behave like an animal or crawl up the chain and behave like a god , it 's our choice . looking back at the sketch , we can see that by changing the position of the man , he can fill the irreconcilable areas of a circle and a square . if geometry is the language the universe is written in , then this sketch seems to say we can exist within all its elements . mankind can fill whatever shape he pleases geometrically and philosophically as well . in this one sketch , leonardo was able to combine the mathematics , religion , philosophy , architecture , and artistic skill of his age . no wonder it has become such an icon for the entire time period .	this led to the creation of mankind , which he placed at the center of the universe with the ability to take whatever form he pleases . mankind , according to pico , could crawl down the chain and behave like an animal or crawl up the chain and behave like a god , it 's our choice . looking back at the sketch , we can see that by changing the position of the man , he can fill the irreconcilable areas of a circle and a square .	where do you think mankind fits on the great chain of being ?
translator : andrea mcdonough reviewer : jessica ruby welcome to the department of plagiarism investigation . the d.p.i . has dealt with numerous complex cases in their effort to bring plagiarists to justice and to rescue purloined texts . the first form of plagiarism that the d.p.i . regularly encounters is known as brain child snatching , in honor of the latin word , plagiarius , from which plagiarism originates . brain child snatchers sneak up on innocent papers and copy and paste them without citing any sources , putting quotation marks around direct quotes or changing a word . they 've also been known to steal and hold particularly eloquent essays for ransom . when brain child snatchers get together , they form a kidnapping ring , which involves brain child snatching from multiple sources . some perpetrators have even been known to commit self-plagiarism , one of the laziest crimes in the annals of the d.p.i . also known as one-sided collaborators , these odd balls snatch up entire texts or small passages that they 've written before and present them as brand-new material . brain child snatchers and kidnapping rings are easy for the d.p.i . to catch . just paste a few passages into a search engine , and bam ! they 're caught red-handed . the more covert forms of plagiarism include the wild goose chase technique , in which plagiarists create fake authors , book titles , page numbers , or other information in order to cover up plagiarism . and the old synonym switcheroo in which plagiarists utilize a thesaurus as their main weapon . by substituting a synonym for nearly every word in the document and leaving the sentence structure and order of the ideas the same , plagiarists give legitimate paraphrasing a very bad name . shoddy paraphrasing is also a key part of variations on a smokescreen , a technique in which multiple passages are paraphrased , then pasted together into one . the thorniest issue that the d.p.i . deals with is the misconception that you can never be accused of plagiarism if you use quotes and cite your sources . this is most certainly not the case because a paper that is made up of passage upon passage of other people 's ideas is known as a wholly quotable document . this is considered plagiarism since there are no original thoughts in the work . similarly , passage after passage of too closely paraphrased text from multiple cited sources is also plagiarism of the pervasively paraphrased kind because the ideas still are n't one 's own . and lastly , the technique of revealing while concealing is plagiarism because it involves selective amnesia regarding one 's sources in an attempt to cover up wholly quotable and pervasively paraphrased issues in a text . some passages are meticulously documented , quoted , or paraphrased , while others are presented entirely as one 's own . as you can see , the d.p.i . has its hands full , tackling all sorts of academic mischief and mayhem , ranging from the petty to the outrageous . given the gravity of these transgressions , you might be wondering why you 've never heard of the department of plagiarism investigation 's victories . that 's because it does n't technically exist . but people , like you and me , can be our own d.p.i . agents to fight plagiarism and uphold the values of original thinking . we know that the best defense against plagiarism consists of writers who save themselves time , worry , and effort by taking the far easier road of just doing the work themselves .	this is considered plagiarism since there are no original thoughts in the work . similarly , passage after passage of too closely paraphrased text from multiple cited sources is also plagiarism of the pervasively paraphrased kind because the ideas still are n't one 's own . and lastly , the technique of revealing while concealing is plagiarism because it involves selective amnesia regarding one 's sources in an attempt to cover up wholly quotable and pervasively paraphrased issues in a text .	trudi takes a properly cited paper that she wrote two years ago for an anthropology course , changes the date in the heading , and turns it in for a history course .
at pixar , we 're all about telling stories , but one story that has n't been told very much is the huge degree to which math is used in the production of our films . the math that you 're learning in middle school and high school is used all the time at pixar . so , let 's start with a very simple example . anybody recognize this guy ? ( cheers ) yeah , so this is woody from toy story , and let 's ask woody to , say , walk across the stage from , say , left to right , just like that . so , believe it or not , you just saw a ton of mathematics . where is it ? well , to explain that , it 's important to understand that artists and designers think in terms of shape and images but computers think in terms of numbers and equations . so , to bridge those two worlds we use a mathematical concept called coordinate geometry , right ? that is , we lay down a coordinate system with x describing how far something is to the right and y describing how high something is . so , with these coordinates we can describe where woody is at any instant in time . for instance , if we know the coordinates of the lower left corner of that image , then we know where the rest of the image is . and in that little sliding animation we saw a second ago , that motion we call translation , the x coordinate started with a value of one , and it ended with a value of about five . so , if we want to write that in mathematics , we see that the x at the end is four bigger than x at the start . so , in other words , the mathematics of translation is addition . alright ? how about scaling ? that is making something bigger or smaller . any guesses as to what the mathematics of scaling might be ? dilation , multiplication , exactly . if you 're going to make something twice as big , you need to mulitply the x and the y coordinates all by two . so , this shows us that the mathematics of scaling is mulitiplication . okay ? how about this one ? how about rotation ? alright , spinning around . the mathematics of rotation is trigonometry . so , here 's an equation that expresses that . it looks a little scary at first . you 'll probably get this in eighth or ninth grade . if you find yourselves sitting in trigonometry class wondering when you 're ever going to need this stuff , just remember that any time you see anything rotate in one of our films , there 's trigonometry at work underneath . i first fell in love with mathematics in seventh grade . any seventh graders ? a few of you ? yeah . my seventh grade science teacher showed me how to use trigonometry to compute how high the rockets that i was building was going . i just thought that was amazing , and i 've been enamored with math ever since . so , this is kind of old mathematics . mathematics that 's been known and , you know , developed by the old dead greek guys . and there 's a myth out there that all the interesting mathematics has already been figured out , in fact all of mathematics has been figured out . but the real story is that new mathematics is being created all the time . and some of it is being created at pixar . so , i 'd like to give you an example of that . so , here are some characters from some of our early films : finding nemo , monsters inc. and toy story 2 . anybody know who the blue character in the upper left is ? it 's dory . okay , that was easy . here 's a little harder one . anybody know who 's the character in the lower right ? al mcwhiggin from al 's toy barn , exactly . the thing to notice about these characters is they 're really complicated . those shapes are really complicated . in fact , the toy cleaner , i have an example , the toy cleaner there in the middle , here 's his hand . you can imagine how fun it was to bring this through airport security . his hand is a really complicated shape . it 's not just a bunch of spheres and cylinders stuck together , right ? and not only is it complicated , but it has to move in complicated ways . so , i 'd like to tell you how we do that , and to do that i need to tell you about midpoints . so , here 's a couple of points , a and b , and the line segment between them . we 're going to start out first in two dimensions . the midpoint , m , is the point that splits that line segment in the middle , right ? so , that 's the geometry . to make equations and numbers , we again introduce a coordinate system , and if we know the coordinates of a and b , we can easily compute the coordinates of m just by averaging . you now know enough to work at pixar . let me show you . so , i 'm going to do something slightly terrifying and move to a live demo here . so , what i have is a four-point polygon here , and it 's going to be my job to make a smooth curve out of this thing . and i 'm going to do it just using the idea of midpoints . so , the first thing i 'm going to do is an operation i 'll call split , which adds midpoints to all those edges . so , i went from four points to eight points , but it 's no smoother . i 'm going to make it a little bit smoother by moving all of these points from where they are now to the midpoint of their clockwise neighbor . so , let me animate that for you . i 'm going to call that the averaging step . so , now i 've got eight points , they 're a little bit smoother , my job is to make a smooth curve , so what do i do ? do it again . split and average . so , now i 've got sixteen points . i 'm going to put those two steps , split and average , together into something i 'll call subdivide , which just means split and then average . so , now i 've got 32 points . if that 's not smooth enough , i 'll do more . i 'll get 64 points . do you see a smooth curve appearing here from those original points ? and that 's how we create the shapes of our charcters . but remember , i said a moment ago it 's not enough just to know the static shape , the fixed shape . we need to animate it . and to animate these curves , the cool thing about subdivision . did you see the aliens in toy story ? you know that sound they make , `` ooh '' ? ready ? so , the way we animate these curves is simply by animating the original four points . `` ooh . '' alright , i think that 's pretty cool , and if you do n't , the door is there , it does n't get any better than that , so . this idea of splitting and averaging also holds for surfaces . so , i 'll split , and i 'll average . i 'll split , and i 'll average . put those together into subdivide , and this how we actually create the shapes of all of our surface characters in three dimensions . so , this idea of subdivision was first used in a short film in 1997 called geri 's game . and geri actually made a cameo apperance in toy story 2 as the toy cleaner . each of his hands was the first time we ever used subdivision . so , each hand was a subdivision surface , his face was a subdivision surface , so was his jacket . here 's geri 's hand before subdivision , and here 's geri 's hand after subdivision , so subdivision just goes in and smooths out all those facets , and creates the beautiful surfaces that you see on the screen and in the theaters . since that time , we 've built all of our characters this way . so , here 's merida , the lead character from brave . her dress was a subdivision surface , her hands , her face . the faces and hands of all the clansman were subdivision surfaces . today we 've seen how addition , multiplication , trigonometry and geometry play a roll in our films . given a little more time , i could show you how linear algebra , differential calculus , integral calculus also play a roll . the main thing i want you to go away with today is to just remember that all the math that you 're learning in high school and actually up through sophomore college we use all the time , everyday , at pixar . thanks .	to make equations and numbers , we again introduce a coordinate system , and if we know the coordinates of a and b , we can easily compute the coordinates of m just by averaging . you now know enough to work at pixar . let me show you .	which pixar characters do you think were the hardest to bring to the screen , and why ? which were the easiest ?
how do you get what you want using just your words ? aristotle set out to answer exactly that question over 2,000 years ago with the treatise on rhetoric . rhetoric , according to aristotle , is the art of seeing the available means of persuasion . and today we apply it to any form of communication . aristotle focused on oration , though , and he described three types of persuasive speech . forensic , or judicial , rhetoric establishes facts and judgements about the past , similar to detectives at a crime scene . epideictic , or demonstrative , rhetoric makes a proclamation about the present situation , as in wedding speeches . but the way to accomplish change is through deliberative rhetoric , or symbouleutikon . rather than the past or the present , deliberative rhetoric focuses on the future . it 's the rhetoric of politicians debating a new law by imagining what effect it might have , like when ronald regan warned that the introduction of medicare would lead to a socialist future spent telling our children and our children 's children what it once was like in america when men were free . but it 's also the rhetoric of activists urging change , such as martin luther king jr 's dream that his children will one day live in a nation where they will not be judged by the color of their skin , but by the content of their character . in both cases , the speaker 's present their audience with a possible future and try to enlist their help in avoiding or achieving it . but what makes for good deliberative rhetoric , besides the future tense ? according to aristotle , there are three persuasive appeals : ethos , logos , and pathos . ethos is how you convince an audience of your credibility . winston churchill began his 1941 address to the u.s. congress by declaring , `` i have been in full harmony all my life with the tides which have flowed on both sides of the atlantic against privilege and monopoly , '' thus highlighting his virtue as someone committed to democracy . much earlier , in his defense of the poet archias , roman consul cicero appealed to his own practical wisdom and expertise as a politician : `` drawn from my study of the liberal sciences and from that careful training to which i admit that at no part of my life i have ever been disinclined . '' and finally , you can demonstrate disinterest , or that you 're not motivated by personal gain . logos is the use of logic and reason . this method can employ rhetorical devices such as analogies , examples , and citations of research or statistics . but it 's not just facts and figures . it 's also the structure and content of the speech itself . the point is to use factual knowledge to convince the audience , as in sojourner truth 's argument for women 's rights : `` i have as much muscle as any man and can do as much work as any man . i have plowed and reaped and husked and chopped and mowed and can any man do more than that ? '' unfortunately , speakers can also manipulate people with false information that the audience thinks is true , such as the debunked but still widely believed claim that vaccines cause autism . and finally , pathos appeals to emotion , and in our age of mass media , it 's often the most effective mode . pathos is neither inherently good nor bad , but it may be irrational and unpredictable . it can just as easily rally people for peace as incite them to war . most advertising , from beauty products that promise to relieve our physical insecurities to cars that make us feel powerful , relies on pathos . aristotle 's rhetorical appeals still remain powerful tools today , but deciding which of them to use is a matter of knowing your audience and purpose , as well as the right place and time . and perhaps just as important is being able to notice when these same methods of persuasion are being used on you .	logos is the use of logic and reason . this method can employ rhetorical devices such as analogies , examples , and citations of research or statistics . but it 's not just facts and figures .	an advertisement that focuses on statistics to sell a product uses :
translator : andrea mcdonough reviewer : jessica ruby mysteries of vernacular : venom , the poisonous fluid secreted by animals , like snakes and scorpions , typically transmitted by bite or sting . as vile as the word is now , the history of venom begins with the pleasant indo-european root wen , which meant to desire or strive for . perhaps , not surprisingly , wen also generated a number of amiable modern words , like win or wish . wenes , a form of the original root , was tailored to the mythology of the time , and applied to the roman goddess of love , venus , known to the greeks as aphrodite and to the egyptians as hathor . from this milieu of amore , the word wenesom emerged , meaning love potion . over time , wenesom became venenum , a word that specifically described potions or medicines that evoked intense physical reactions from the patient . the definition of venenum eventually narrowed to refer solely to poisonous concoctions , a shift that puts us within striking distance of the word under investigation . a bit of shortening and a slight distinction in source brings us to venom , a deadly fluid that comes from a snake rather than a pharmacist .	translator : andrea mcdonough reviewer : jessica ruby mysteries of vernacular : venom , the poisonous fluid secreted by animals , like snakes and scorpions , typically transmitted by bite or sting . as vile as the word is now , the history of venom begins with the pleasant indo-european root wen , which meant to desire or strive for . perhaps , not surprisingly , wen also generated a number of amiable modern words , like win or wish .	what does the word wen mean ?
translator : joseph geni reviewer : morton bast growing up in taiwan as the daughter of a calligrapher , one of my most treasured memories was my mother showing me the beauty , the shape and the form of chinese characters . ever since then , i was fascinated by this incredible language . but to an outsider , it seems to be as impenetrable as the great wall of china . over the past few years , i 've been wondering if i can break down this wall , so anyone who wants to understand and appreciate the beauty of this sophisticated language could do so . i started thinking about how a new , fast method of learning chinese might be useful . since the age of five , i started to learn how to draw every single stroke for each character in the correct sequence . i learned new characters every day during the course of the next 15 years . since we only have five minutes , it 's better that we have a fast and simpler way . a chinese scholar would understand 20,000 characters . you only need 1,000 to understand the basic literacy . the top 200 will allow you to comprehend 40 percent of basic literature -- enough to read road signs , restaurant menus , to understand the basic idea of the web pages or the newspapers . today i 'm going to start with eight to show you how the method works . you are ready ? open your mouth as wide as possible until it 's square . you get a mouth . this is a person going for a walk . person . if the shape of the fire is a person with two arms on both sides , as if she was yelling frantically , `` help ! i 'm on fire ! '' -- this symbol actually is originally from the shape of the flame , but i like to think that way . whichever works for you . this is a tree . tree . this is a mountain . the sun . the moon . the symbol of the door looks like a pair of saloon doors in the wild west . i call these eight characters radicals . they are the building blocks for you to create lots more characters . a person . if someone walks behind , that is `` to follow . '' as the old saying goes , two is company , three is a crowd . if a person stretched their arms wide , this person is saying , `` it was this big . '' the person inside the mouth , the person is trapped . he 's a prisoner , just like jonah inside the whale . one tree is a tree . two trees together , we have the woods . three trees together , we create the forest . put a plank underneath the tree , we have the foundation . put a mouth on the top of the tree , that 's `` idiot . '' ( laughter ) easy to remember , since a talking tree is pretty idiotic . remember fire ? two fires together , i get really hot . three fires together , that 's a lot of flames . set the fire underneath the two trees , it 's burning . for us , the sun is the source of prosperity . two suns together , prosperous . three together , that 's sparkles . put the sun and the moon shining together , it 's brightness . it also means tomorrow , after a day and a night . the sun is coming up above the horizon . sunrise . a door . put a plank inside the door , it 's a door bolt . put a mouth inside the door , asking questions . knock knock . is anyone home ? this person is sneaking out of a door , escaping , evading . on the left , we have a woman . two women together , they have an argument . ( laughter ) three women together , be careful , it 's adultery . so we have gone through almost 30 characters . by using this method , the first eight radicals will allow you to build 32 . the next group of eight characters will build an extra 32 . so with very little effort , you will be able to learn a couple hundred characters , which is the same as a chinese eight-year-old . so after we know the characters , we start building phrases . for example , the mountain and the fire together , we have fire mountain . it 's a volcano . we know japan is the land of the rising sun . this is a sun placed with the origin , because japan lies to the east of china . so a sun , origin together , we build japan . a person behind japan , what do we get ? a japanese person . the character on the left is two mountains stacked on top of each other . in ancient china , that means in exile , because chinese emperors , they put their political enemies in exile beyond mountains . nowadays , exile has turned into getting out . a mouth which tells you where to get out is an exit . this is a slide to remind me that i should stop talking and get off of the stage . thank you . ( applause )	the symbol of the door looks like a pair of saloon doors in the wild west . i call these eight characters radicals . they are the building blocks for you to create lots more characters .	practice the first eight characters that shaolan describes , which she calls `` radicals . ''
if you 're ever walking down the street and come across an oddly stretched out image , like this , you 'll have an opportunity to see something remarkable , but only if you stand in exactly the right spot . that happens because these works employ a technique called anamorphosis . anamorphosis is a special case of perspective art , where artists represent realistic three-dimensional views on two-dimensional surfaces . though it 's common today , this kind of perspective drawing has only been around since the italian renaissance . ancient art often showed all figures on the same plane , varying in size by symbolic importance . classical greek and roman artists realized they could make objects seem further by drawing them smaller , but many early attempts at perspective were inconsistent or incorrect . in 15th century florence , artists realized the illusion of perspective could be achieved with higher degrees of sophistication by applying mathematical principles . in 1485 , leonardo da vinci manipulated the mathematics to create the first known anamorphic drawing . a number of other artists later picked up the technique , including hans holbein in `` the ambassadors . '' this painting features a distorted shape that forms into a skull as the viewer approaches from the side . in order to understand how artists achieve that effect , we first have to understand how perspective drawings work in general . imagine looking out a window . light bounces off objects and into your eye , intersecting the window along the way . now , imagine you could paint the image you see directly onto the window while standing still and keeping only one eye open . the result would be nearly indistinguishable from the actual view with your brain adding depth to the 2-d picture , but only from that one spot . standing even just a bit off to the side would make the drawing lose its 3-d effect . artists understand that a perspective drawing is just a projection onto a 2-d plane . this allows them to use math to come up with basic rules of perspective that allow them to draw without a window . one is that parallel lines , like these , can only be drawn as parallel if they 're parallel to the plane of the canvas . otherwise , they need to be drawn converging to a common point known as the vanishing point . so that 's a standard perspective drawing . with an anamorphic drawing , like `` the ambassadors , '' directly facing the canvas makes the image look stretched and distorted , but put your eye in exactly the right spot way off to the side , and the skull materializes . going back to the window analogy , it 's as if the artist painted onto a window positioned at an angle instead of straight on , though that 's not how renaissance artists actually created anamorphic drawings . typically , they draw a normal image onto one surface , then use a light , a grid , or even strings to project it onto a canvas at an angle . now let 's say you want to make an anamorphic sidewalk drawing . in this case , you want to create the illusion that a 3-d image has been added seamlessly into an existing scene . you can first put a window in front of the sidewalk and draw what you want to add onto the window . it should be in the same perspective as the rest of the scene , which might require the use of those basic rules of perspective . once the drawing 's complete , you can use a projector placed where your eye was to project your drawing down onto the sidewalk , then chalk over it . the sidewalk drawing and the drawing on the window will be nearly indistinguishable from that point of view , so viewers ' brains will again be tricked into believing that the drawing on the ground is three-dimensional . and you do n't have to project onto a flat surface to create this illusion . you can project onto multiple surfaces , or assemble a jumble of objects , that from the right point of view , appears to be something else entirely . all over the planet , you can find solid surfaces giving way to strange , wonderful , or terrifying visions . from your sidewalk to your computer screen , these are just some of the ways that math and perspective can open up whole new worlds .	otherwise , they need to be drawn converging to a common point known as the vanishing point . so that 's a standard perspective drawing . with an anamorphic drawing , like `` the ambassadors , '' directly facing the canvas makes the image look stretched and distorted , but put your eye in exactly the right spot way off to the side , and the skull materializes .	perspective drawing is one area of art in which mathematics is a necessary and integral part of the art-making process . in what other creative areas is mathematics used ? give some examples in areas such as theater , music , industrial design , sculpture , etc .
in 1861 , two scientists got into a very brainy argument . specifically , they had opposing ideas of how speech and memory operated within the human brain . ernest aubertin , with his localistic model , argued that a particular region or the brain was devoted to each separate process . pierre gratiolet , on the other hand , argued for the distributed model , where different regions work together to accomplish all of these various functions . the debate they began reverberated throughout the rest of the century , involving some of the greatest scientific minds of the time . aubertin and his localistic model had some big names on his side . in the 17th century , rené descartes had assigned the quality of free will and the human soul to the pineal gland . and in the late 18th century , a young student named franz joseph gall had observed that the best memorizers in his class had the most prominent eyes and decided that this was due to higher development in the adjacent part of the brain . as a physician , gall went on to establish the study of phrenology , which held that strong mental faculties corresponded to highly developed brain regions , observable as bumps in the skull . the widespread popularity of phrenology throughout the early 19th century tipped the scales towards aubertin 's localism . but the problem was that gall had never bothered to scientifically test whether the individual brain maps he had constructed applied to all people . and in the 1840 's , pierre flourens challenged phrenology by selectively destroying parts of animal brains and observing which functions were lost . flourens found that damaging the cortex interfered with judgement or movement in general , but failed to identify any region associated with one specific function , concluding that the cortex carried out brain functions as an entire unit . flourens had scored a victory for gratiolet , but it was not to last . gall 's former student , jean-baptiste bouillaud , challenged flourens ' conclusion , observing that patients with speech disorders all had damage to the frontal lobe . and after paul broca 's 1861 autopsy of a patient who had lost the power to produce speech , but not the power to understand it , revealed highly localized frontal lobe damage , the distributed model seemed doomed . localism took off . in the 1870 's , karl wernicke associated part of the left temporal lobe with speech comprehension . soon after , eduard hitzig and gustav fritsch stimulated a dog 's cortex and discovered a frontal lobe region responsible for muscular movements . building on their work , david ferrier mapped each piece of cortex associated with moving a part of the body . and in 1909 , korbinian brodmann built his own cortex map with 52 separate areas . it appeared that the victory of aubertin 's localistic model was sealed . but neurologist karl wernicke had come up with an interesting idea . he reasoned that since the regions for speech production and comprehension were not adjacent , then injuring the area connecting them might result in a special type of language loss , now known as receptive aphasia . wernicke 's connectionist model helped explain disorders that did n't result from the dysfunction of just one area . modern neuroscience tools reveal a brain more complex than gratiolet , aubertin , or even wernicke imagined . today , the hippocampus is associated with two distinct brain functions : creating memories and processing location in space . we also now measure two kinds of connectivity : anatomical connectivity between two adjoining regions of cortex working together , and functional connectivity between separated regions working together to accomplish one process . a seemingly basic function like vision is actually composed of many smaller functions , with different parts of the cortex representing shape , color and location in space . when certain areas stop functioning , we may recognize an object , but not see it , or vice versa . there are even different kinds of memory for facts and for routines . and remembering something like your first bicycle involves a network of different regions each representing the concept of vehicles , the bicycle 's shape , the sound of the bell , and the emotions associated with that memory . in the end , both gratiolet and aubertin turned out to be right . and we still use both of their models to understand how cognition happens . for example , we can now measure brain activity on such a fine time scale that we can see the individual localized processes that comprise a single act of remembering . but it is the integration of these different processes and regions that creates the coherent memory we experience . the supposedly competing theories prove to be two aspects of a more comprehensive model , which will in turn be revised and refined as our scientific techologies and methods for understanding the brain improve .	and in the late 18th century , a young student named franz joseph gall had observed that the best memorizers in his class had the most prominent eyes and decided that this was due to higher development in the adjacent part of the brain . as a physician , gall went on to establish the study of phrenology , which held that strong mental faculties corresponded to highly developed brain regions , observable as bumps in the skull . the widespread popularity of phrenology throughout the early 19th century tipped the scales towards aubertin 's localism .	gall ’ s once popular method of measuring the skull to determine a person ’ s strong and weak mental faculties did not hold up to scrutiny and is now known to be pseudoscience . why didn ’ t it hold up and why should this matter ?
how do schools of fish swim in harmony ? and how do the tiny cells in your brain give rise to the complex thoughts , memories , and consciousness that are you ? oddly enough , those questions have the same general answer : emergence , or the spontaneous creation of sophisticated behaviors and functions from large groups of simple elements . like many animals , fish stick together in groups , but that 's not just because they enjoy each other 's company . it 's a matter of survival . schools of fish exhibit complex swarming behaviors that help them evade hungry predators , while a lone fish is quickly singled out as easy prey . so which brilliant fish leader is the one in charge ? actually , no one is , and everyone is . so what does that mean ? while the school of fish is elegantly twisting , turning , and dodging sharks in what looks like deliberate coordination , each individual fish is actually just following two basic rules that have nothing to do with the shark : one , stay close , but not too close to your neighbor , and two , keep swimmming . as individuals , the fish are focused on the minutiae of these local interactions , but if enough fish join the group , something remarkable happens . the movement of individual fish is eclipsed by an entirely new entity : the school , which has its own unique set of behaviors . the school is n't controlled by any single fish . it simply emerges if you have enough fish following the right set of local rules . it 's like an accident that happens over and over again , allowing fish all across the ocean to reliably avoid predation . and it 's not just fish . emergence is a basic property of many complex systems of interacting elements . for example , the specific way in which millions of grains of sand collide and tumble over each other almost always produces the same basic pattern of ripples . and when moisture freezes in the atmosphere , the specific binding properties of water molecules reliably produce radiating lattices that form into beautiful snowflakes . what makes emergence so complex is that you ca n't understand it by simply taking it apart , like the engine of a car . taking things apart is a good first step to understanding a complex system . but if you reduce a school of fish to individuals , it loses the ability to evade predators , and there 's nothing left to study . and if you reduce the brain to individual neurons , you 're left with something that is notoriously unreliable , and nothing like how we think and behave , at least most of the time . regardless , whatever you 're thinking about right now is n't reliant on a single neuron lodged in the corner of your brain . rather , the mind emerges from the collective activities of many , many neurons . there are billions of neurons in the human brain , and trillions of connections between all those neurons . when you turn such a complicated system like that on , it could behave in all sorts of weird ways , but it does n't . the neurons in our brain follow simple rules , just like the fish , so that as a group , their activity self-organizes into reliable patterns that let you do things like recognize faces , successfully repeat the same task over and over again , and keep all those silly little habits that everyone likes about you . so , what are the simple rules when it comes to the brain ? the basic function of each neuron in the brain is to either excite or inhibit other neurons . if you connect a few neurons together into a simple circuit , you can generate rhythmic patterns of activity , feedback loops that ramp up or shut down a signal , coincidence detectors , and disinhibition , where two inhibitory neurons can actually activate another neuron by removing inhibitory brakes . as more and more neurons are connected , increasingly complex patterns of activity emerge from the network . soon , so many neurons are interacting in so many different ways at once that the system becomes chaotic . the trajectory of the network 's activity can not be easily explained by the simple local circuits described earlier . and yet , from this chaos , patterns can emerge , and then emerge again and again in a reproducible manner . at some point , these emergent patterns of activity become sufficiently complex , and curious to begin studying their own biological origins , not to mention emergence . and what we found in emergent phenomena at vastly different scales is that same remarkable characteristic as the fish displayed : that emergence does n't require someone or something to be in charge . if the right rules are in place , and some basic conditions are met , a complex system will fall into the same habits over and over again , turning chaos into order . that 's true in the molecular pandemonium that lets your cells function , the tangled thicket of neurons that produces your thoughts and identity , your network of friends and family , all the way up to the structures and economies of our cities across the planet .	what makes emergence so complex is that you ca n't understand it by simply taking it apart , like the engine of a car . taking things apart is a good first step to understanding a complex system . but if you reduce a school of fish to individuals , it loses the ability to evade predators , and there 's nothing left to study .	imagine you travel to another planet , and discover a completely new form of life . you know absolutely nothing about them . how would you go about studying these creatures ? what would be the first thing you ’ d want to know about them ? what questions could you then ask once you knew more about them ?
have you ever wondered what happens to a painkiller , like ibuprofen , after you swallow it ? medicine that slides down your throat can help treat a headache , a sore back , or a throbbing sprained ankle . but how does it get where it needs to go in the first place ? the answer is that it hitches a ride in your circulatory blood stream , cycling through your body in a race to do its job before it 's snared by organs and molecules designed to neutralize and expel foreign substances . this process starts in your digestive system . say you swallow an ibuprofen tablet for a sore ankle . within minutes , the tablet starts disintegrating in the acidic fluids of your stomach . the dissolved ibuprofen travels into the small intestine and then across the intestinal wall into a network of blood vessels . these blood vessels feed into a vein , which carries the blood , and anything in it , to the liver . the next step is to make it through the liver . as the blood and the drug molecules in it travel through liver blood vessels , enzymes attempt to react with the ibuprofen molecules to neutralize them . the damaged ibuprofen molecules , called metabolites , may no longer be effective as painkillers . at this stage , most of the ibuprofen makes it through the liver unscathed . it continues its journey out of the liver , through veins , into the body 's circulatory system . half an hour after you swallow the pill , some of the dose has already made it into the circulatory blood stream . this blood loop travels through every limb and organ , including the heart , brain , kidneys , and back through the liver . when ibuprofen molecules encounter a location where the body 's pain response is in full swing , they bind to specific target molecules that are a part of that reaction . painkillers , like ibuprofen , block the production of compounds that help the body transmit pain signals . as more drug molecules accumulate , the pain-cancelling affect increases , reaching a maximum within about one or two hours . then the body starts efficiently eliminating ibuprofen , with the blood dose decreasing by half every two hours on average . when the ibuprofen molecules detach from their targets , the systemic blood stream carries them away again . back in the liver , another small fraction of the total amount of the drug gets transformed into metabolites , which are eventually filtered out by the kidneys in the urine . the loop from liver to body to kidneys continues at a rate of about one blood cycle per minute , with a little more of the drug neutralized and filtered out in each cycle . these basic steps are the same for any drug that you take orally , but the speed of the process and the amount of medicine that makes it into your blood stream varies based on drug , person , and how it gets into the body . the dosing instructions on medicine labels can help , but they 're averages based on a sample population that does n't represent every consumer . and getting the dose right is important . if it 's too low , the medicine wo n't do its job . if it 's too high , the drug and its metabolites can be toxic . that 's true of any drug . one of the hardest groups of patients to get the right dosage for are children . that 's because how they process medicine changes quickly , as do their bodies . for instance , the level of liver enzymes that neutralize medication highly fluctuates during infancy and childhood . and that 's just one of many complicating factors . genetics , age , diet , disease , and even pregnancy influence the body 's efficiency of processing medicine . some day , routine dna tests may be able to dial in the precise dose of medicine personalized to your liver efficiency and other factors , but in the meantime , your best bet is reading the label or consulting your doctor or pharmacist , and taking the recommended amounts with the recommended timing .	and that 's just one of many complicating factors . genetics , age , diet , disease , and even pregnancy influence the body 's efficiency of processing medicine . some day , routine dna tests may be able to dial in the precise dose of medicine personalized to your liver efficiency and other factors , but in the meantime , your best bet is reading the label or consulting your doctor or pharmacist , and taking the recommended amounts with the recommended timing .	a drug/medicine taken as a tablet can eventually treat any part of the body because it reaches the _________ that goes everywhere in the body .
when reverend jim jones founded the peoples temple in 1955 , few could have imagined its horrifying end . this progressive religious movement rose in popularity and gained support from some of san francisco 's most prominent politicians . but in 1977 , amidst revelations of brainwashing and abuse , jones moved with several hundred followers to establish the commune of jonestown in guyana . billed as a utopian paradise , the colony was more like a prison camp , and when a congressional delegation arrived to investigate its conditions , jones executed his final plan . on november 18 , 1978 , 909 men , women , and children died after being forced to drink poisoned flavor aid . that grizzly image has since been immortalized as shorthand slang for single-minded cult-like thinking , `` they drank the kool-aid . '' today , there are thousands of cults around the world . it 's important to note two things about them . first , not all cults are religious . some are political , therapy-based , focused on self-improvement , or otherwise . and on the flip side , not all new religions are what we 're referring to as cults . so what exactly defines our modern understanding of cults , and why do people join them ? broadly speaking , a cult is a group or movement with a shared commitment to a usually extreme ideology that 's typically embodied in a charismatic leader . and while few turn out as deadly as jonestown or heaven 's gate , which ended in a mass suicide of 39 people in 1997 , most cults share some basic characteristics . a typical cult requires a high level of commitment from its members and maintains a strict hierarchy , separating unsuspecting supporters and recruits from the inner workings . it claims to provide answers to life 's biggest questions through its doctrine , along with the required recipe for change that shapes a new member into a true believer . and most importantly , it uses both formal and informal systems of influence and control to keep members obedient , with little tolerance for internal disagreement or external scrutiny . you might wonder whether some of these descriptions might also apply to established religions . in fact , the world `` cultus '' originally described people who cultivated the worship of certain gods by performing rituals and maintaining temples . but in time , it came to mean excessive devotion . many religions began as cults , but integrated into the fabric of the larger society as they grew . a modern cult , by contrast , separates its members from others . rather than providing guidelines for members to live better lives , a cult seeks to directly control them , from personal and family relationships , to financial assets and living arrangements . cults also demand obedience to human leaders who tend to be highly persuasive people with authoritarian and narcissistic streaks motivated by money , sex , power , or all three . while a cult leader uses personal charisma to attract initial followers , further expansion works like a pyramid scheme , with early members recruiting new ones . cults are skilled at knowing whom to target , often focusing on those new to an area , or who have recently undergone some personal or professional loss . loneliness and a desire for meaning make one susceptible to friendly people offering community . the recruitment process can be subtle , sometimes taking months to establish a relationship . in fact , more than two-thirds of cult members are recruited by a friend , family member , or co-worker whose invitations are harder to refuse . once in the cult , members are subjected to multiple forms of indoctrination . some play on our natural inclination to mimic social behaviors or follow orders . other methods may be more intense using techniques of coercive persuasion involving guilt , shame , and fear . and in many cases , members may willingly submit out of desire to belong and to attain the promised rewards . the cult environment discourages critical thinking , making it hard to voice doubts when everyone around you is modeling absolute faith . the resulting internal conflict , known as cognitive dissonance , keeps you trapped , as each compromise makes it more painful to admit you 've been deceived . and though most cults do n't lead members to their death , they can still be harmful . by denying basic freedoms of thought , speech , and association , cults stunt their members ' psychological and emotional growth , a particular problem for children , who are deprived of normal developmental activities and milestones . nevertheless , many cult members eventually find a way out , whether through their own realizations , the help of family and friends , or when the cult falls apart due to external pressure or scandals . many cults may be hard to identify , and for some , their beliefs , no matter how strange , are protected under religious freedom . but when their practices involve harassment , threats , illegal activities , or abuse , the law can intervene . believing in something should not come at the cost of your family and friends , and if someone tells you to sacrifice your relationships or morality for the greater good , they 're most likely exploiting you for their own .	it 's important to note two things about them . first , not all cults are religious . some are political , therapy-based , focused on self-improvement , or otherwise .	all cults are religious .
today lots of girls play sports . but , for a long time , girls were not encouraged to kick , throw , run , jump , shoot , slide , or hit like boys . so , why did things change ? and how much have they changed ? are girls and boys treated equally when it comes to sports ? to begin to answer these questions , we have to look back . in 1972 , congress passed a law called title ix , which protected girls and women from discrimination in schools , colleges , and universities . this included discrimination in school-sponsored sports . at that time , only 15 % of college athletes were women , and in high schools , only 7 % of athletes were girls . female athletes did n't get a lot of support either and often had to provide their own uniforms and equipment . it was title ix that forced school administrators to make sports more equal . but what does equal mean in sports ? the government developed rules to measure equality under two general categories : participation and treatment . in the early days of title ix , the number of girls playing sports was so low that it would have been very difficult for schools to suddenly provide exactly the same number of opportunities for girls and boys . instead , the government wrote rules that gave schools three options , or tests , to demonstrate fairness in opportunities for girls . the three tests are proportionality , progress , and satisfied interests . a school can pick which test to follow . proportionality means that girls should receive the same percentage of athletic opportunities as the percentage of girls in the student body . so , if 51 % of students are girls , then girls should have approximately 51 % of the opportunities to play sports . the second test , progress , requires schools to make up for the days when girls had fewer opportunities by adding new sports for girls on a regular basis . the third test asks if girls interested in athletics are satisfied . under this test , a school must regularly ask female students what sports they are interested in and also take into consideration the popularity of certain sports in the area where the school is located . it must , then , add teams according to the girls ' interests . another important part of title ix is that it does n't just look at how many athletic opportunities are available to each sex but whether those opportunities are of equal quality . specifically , title ix requires equality between boys and girls teams for things like equipment and supplies , publicity , the scheduling of games and practice times , and the quality and number of coaches . girls should also have equal access to locker rooms , practice spaces , and competitive facilities , as well as medical services . so , if the best time to play basketball is on friday nights because that 's when most parents and fans can come , then the girls and boys teams should take turns playing on friday night . if boys teams play in a stadium with lights , scoreboards , and concession stands , then girls teams must have the same opportunity , either by sharing those facilities or getting their own of equal quality . but , as we all know , just because a law exists does n't mean that everybody follows it . school officials are responsible for making sure there is fairness in sports , but you can help , too , by keeping an eye on your own school . look around . are there a lot more boys than girls who play sports ? is the boys ' soccer field better than the girls ' ? are athletic trainers available to all teams equally ? does the baseball team get new uniforms every year , while the softball team gets them every three years ? if you think there might be inequality in your schools , you can approach a school administrator , a parent , or the office of civil rights , a government agency that makes sure schools comply with title ix because equality is important for everyone , both on the field and off .	female athletes did n't get a lot of support either and often had to provide their own uniforms and equipment . it was title ix that forced school administrators to make sports more equal . but what does equal mean in sports ?	to what activities does title ix apply ?
in this short video , we 're going to show you how we use two different animation techniques , both rotoscoping and traditional hand-drawn animation in the ted-ed lesson , `` miss gayle 's 5 steps to slam poetry : a lesson of transformation . '' a poetry slam is a competition in which poets are judged on their poems , often for qualities of emotional power and lyrical resonance . our lesson was created by gayle danley , a veteran slam poet who spent decades teaching children to express themselves through spoken words , a lesson , which offers a guide to creating poetry with immediacy and power , also serves as a great example of exactly that . it 's a story told in the form of a poem that packs a real emotional punch . she introduces tyler , who 's sitting in an 11th grade writing class , struggling with the assignment of having to write a poem based on a personal experience . the story is told from two perspectives , one external and one internal . miss gayle 's narration sets the stage of the outside world , and spoken word artist pages d. matan performs tyler 's inner voice . to set these two realms of inner- and outer-experience apart , a different animation technique was used to illustrate each . the real world was animated by rotoscoping , with a frame-by-frame tracing of live-action footage in black and white line art . the animation depicting the inner-stream of consciousness world of tyler 's memories was traditionally drawn on paper , featured watercolored backgrounds and a more expressionistic design . once deciding on this general approach , the project went right into pre-production . in animation , pre-production is the planning stage . it 's all the decisions that need to be made before going and actually making the thing in its final form . this can include developing the look or design of the piece , experimenting with colors and camera angles , revising the script , and so on . all these decisions are important because they determine how much work and time the production will take . extra time spent here figuring things out can often save a lot of time down the road . for our project , a storyboard was first created , in which the framing , composition , and imagery for each shot was determined . then an animatic was made , which is basically a movie of the storyboard . this helped us figure out the timing of each shot . it also helped us get an idea of how well everything would flow together visually between our rotoscoped and traditionally animated scenes once they were assembled . for the rotoscoped shots , we first had to create the live action footage to be traced . working with what we had in our humble office , we created a classroom of desks using only one small table . we shot this multiple times from each angle the storyboard called for , each time with a different volunteer from among our co-workers . our source footage elements then needed to be composited , or assembled and arranged together , before we could rotoscope them . a composite is a special effects term for a shot that combines two or more elements in it that were created separately . to do this , we used after effects , a digital compositing and motion graphics program . the first step was to isolate the part of the frame we needed by masking off the unnecessary negative space , or parts of the frame we did n't need . the individual shots were then each layered into one composite shot , resized and arranged appropriately to create the illusion of them all being there in perspective at the same time . every third frame was then exported as an image sequence , ready to be rotoscoped . the tracing was done digitally , drawn directly on a cintiq monitor . the rest of the animation was done by hand on paper . unlike rotoscoping , here the timing and motion of the animation was all planned out by the animator ahead of time . an appropriate number of drawings were then done to accomplish the movement . each animation drawing is then scanned , registered , and sequenced together in the computer . that animation sequence is then composited with the layered background art . camera moves are then plotted out and executed . one way that poetry uses language to communicate emotions and ideas is through the use of metaphor . `` mama 's lies are footsteps too many to count making excuses on black snow . '' animation 's a medium that 's also uniquely well-suited to communicating emotions and ideas through visual metaphor . applying the dual techniques of rotoscoped and traditional animation , each with their own inherent looks , allowed us to visually represent the dual nature of the creative process described in the lesson . there 's the internal aspect of experience and memory , which is mined for inspiration , and there 's the external aspect of revealing it to the world through a structured presentation . we combined both techniques for the last shots of tyler delivering his poem to the world , allowing us to convey in a direct , visual way the power of that moment of communication when internal becomes external , which , in both poetry and animation , is where the magic happens .	a poetry slam is a competition in which poets are judged on their poems , often for qualities of emotional power and lyrical resonance . our lesson was created by gayle danley , a veteran slam poet who spent decades teaching children to express themselves through spoken words , a lesson , which offers a guide to creating poetry with immediacy and power , also serves as a great example of exactly that . it 's a story told in the form of a poem that packs a real emotional punch .	what best describes gayle danley ?
why does salt dissolve in water but oil does n't ? well , in a word , chemistry , but that 's not very satisfying , is it ? well , the reason salt dissolves and oil does not comes down to the two big reasons why anything happens at all : energetics and entropy . energetics deals primarily with the attractive forces between things . when we look at oil or salt in water , we focus on the forces between particles on a very , very , very small scale , the molecular level . to give you a sense of this scale , in one glass of water , there are more molecules than known stars in the universe . now , all of these molecules are in constant motion , moving , vibrating , and rotating . what prevents almost all of those molecules from just flying out of the glass are the attractive interactions between molecules . the strength of the interactions between water , itself , and other substances is what we mean when we say energetics . you can think of the water molecules engaging in a constant dance , sort of like a square dance where they constantly and randomly exchange partners . put simply , the ability for substances to interact with water , balanced with how they disrupt how water interacts with itself , plays an important role in explaining why certain things mix well into water and others do n't . entropy basically describes the way things and energy can be arranged based on random motion . for example , think of the air in a room . imagine all the different possible arrangements in space for the trillions of particles that make up the air . some of those arrangments might have all the oxygen molecules over here and all the nitrogen molecules over there , separated . but far more of the possible arrangements have those molecules mixed up with one another . so , entropy favors mixing . energetics deals with attractive forces . and so , if attractive forces are present , the probability of some arrangements can be enhanced , the ones where things are attracted to each other . so , it is always the balance of these two things that determines what happens . on the molecular level , water is comprised of water molecules , made up of two hydrogen atoms and an oxygen atom . as liquid water , these molecules are engaged in a constant and random square dance that is called the hydrogen bonding network . entropy favors keeping the square dance going at all times . there are always more ways that all the water molecules can arrange in a square dance , as compared to if the water molecules did a line dance . so , the square dance constantly goes on . so , what happens when you put salt in the water ? well , on the molecular level , salt is actually made up of two different ions , chlorine and sodium , that are organized like a brick wall . they show up to the dance as a big group in formation and sit on the side at first , shy and a bit reluctant to break apart into individual ions to join the dance . but secretly , those shy dancers just want someone to ask them to join . so , when a water randomly bumps into one of them and pulls them into the dance away from their group , they go . and once they go into the dance , they do n't come back out . and in fact , the addition of the salt ions adds more possible dance positions in the square dance , so it is favored for them to stay dancing with water . now , let 's take oil . with oil , the molecules are sort of interested in dancing with water , so entropy favors them joining the dance . the problem is that oil molecules are wearing gigantic ballgowns , and they 're way bigger than water molecules . so , when an oil molecule gets pulled in , their size is really disruptive to the dance and the random exchange of partners that the waters engage in , a very important part of the dance . in addition , they are not great dancers . the water molecules try to engage the oil molecules in the dance , but they just keep bumping into their dresses and taking up all the room on the dance floor . there are way more ways the waters can dance when the oil gets off the floor , so the waters squeeze out the oil , pushing it back to the bench with the others . pretty soon , when a large number of oils have been squeezed over to the side , they band together to commiserate about how unfair the waters are being and stick together as a group . so , it is this combination of the interactions between molecules and the configurations available to them when they 're moving randomly that dictates whether they mix . in other words , water and oil do n't mix because they just do n't make great dance partners .	so , entropy favors mixing . energetics deals with attractive forces . and so , if attractive forces are present , the probability of some arrangements can be enhanced , the ones where things are attracted to each other .	energetics deals with ________ .
many people in the united states and latin america have grown up celebrating the anniversary of christopher columbus 's voyage , but was he an intrepid explorer who brought two worlds together or a ruthless exploiter who brought colonialism and slavery ? and did he even discover america at all ? it 's time to put columbus on the stand in history vs. christopher columbus . `` order , order in the court . wait , am i even supposed to be at work today ? '' cough `` yes , your honor . from 1792 , columbus day was celebrated in many parts of the united states on october 12th , the actual anniversary date . but although it was declared an official holiday in 1934 , individual states are n't required to observe it . only 23 states close public services , and more states are moving away from it completely . '' cough `` what a pity . in the 70s , we even moved it to the second monday in october so people could get a nice three-day weekend , but i guess you folks just hate celebrations . '' `` uh , what are we celebrating again ? '' `` come on , your honor , we all learned it in school . christopher columbus convinced the king of spain to send him on a mission to find a better trade route to india , not by going east over land but sailing west around the globe . everyone said it was crazy because they still thought the world was flat , but he knew better . and when in 1492 he sailed the ocean blue , he found something better than india : a whole new continent . '' `` what rubbish . first of all , educated people knew the world was round since aristotle . secondly , columbus did n't discover anything . there were already people living here for millennia . and he was n't even the first european to visit . the norse had settled newfoundland almost 500 years before . '' `` you do n't say , so how come we 're not all wearing those cow helmets ? '' `` actually , they did n't really wear those either . '' cough `` who cares what some vikings did way back when ? those settlements did n't last , but columbus 's did . and the news he brought back to europe spread far and wide , inspiring all the explorers and settlers who came after . without him , none of us would be here today . '' `` and because of him , millions of native americans are n't here today . do you know what columbus did in the colonies he founded ? he took the very first natives he met prisoner and wrote in his journal about how easily he could conquer and enslave all of them . '' `` oh , come on . everyone was fighting each other back then . did n't the natives even tell columbus about other tribes raiding and taking captives ? '' `` yes , but tribal warfare was sporadic and limited . it certainly did n't wipe out 90 % of the population . '' `` hmm . why is celebrating this columbus so important to you , anyway ? '' `` your honor , columbus 's voyage was an inspiration to struggling people all across europe , symbolizing freedom and new beginnings . and his discovery gave our grandparents and great-grandparents the chance to come here and build better lives for their children . do n't we deserve a hero to remind everyone that our country was build on the struggles of immigrants ? '' `` and what about the struggles of native americans who were nearly wiped out and forced into reservations and whose descendants still suffer from poverty and discrimination ? how can you make a hero out of a man who caused so much suffering ? '' `` that 's history . you ca n't judge a guy in the 15th century by modern standards . people back then even thought spreading christianity and civilization across the world was a moral duty . '' `` actually , he was pretty bad , even by old standards . while governing hispaniola , he tortured and mutilated natives who did n't bring him enough gold and sold girls as young as nine into sexual slavery , and he was brutal even to the other colonists he ruled , to the point that he was removed from power and thrown in jail . when the missionary , bartolomé de las casas , visited the island , he wrote , 'from 1494 to 1508 , over 3,000,000 people had perished from war , slavery and the mines . who in future generations will believe this ? ' '' `` well , i 'm not sure i believe those numbers . '' `` say , are n't there other ways the holiday is celebrated ? '' `` in some latin american countries , they celebrate the same date under different names , such as día de la raza . in these places , it 's more a celebration of the native and mixed cultures that survived through the colonial period . some places in the u.s. have also renamed the holiday , as native american day or indigenous people 's day and changed the celebrations accordingly . '' `` so , why not just change the name if it 's such a problem ? '' `` because it 's tradition . ordinary people need their heroes and their founding myths . ca n't we just keep celebrating the way we 've been doing for a century , without having to delve into all this serious research ? it 's not like anyone is actually celebrating genocide . '' `` traditions change , and the way we choose to keep them alive says a lot about our values . '' `` well , it looks like giving tired judges a day off is n't one of those values , anyway . '' traditions and holidays are important to all cultures , but a hero in one era may become a villain in the next as our historical knowledge expands and our values evolve . and deciding what these traditions should mean today is a major part of putting history on trial .	`` that 's history . you ca n't judge a guy in the 15th century by modern standards . people back then even thought spreading christianity and civilization across the world was a moral duty . '' `` actually , he was pretty bad , even by old standards . while governing hispaniola , he tortured and mutilated natives who did n't bring him enough gold and sold girls as young as nine into sexual slavery , and he was brutal even to the other colonists he ruled , to the point that he was removed from power and thrown in jail .	do humanity ’ s moral standards change with time , or are there certain things that would shock people in any era ?
( music ) esteemed members of the jury , i submit the following words for immediate and violent execution and extraction from our vocabularies , to be locked away forever , if you would prefer . these words i present to you are `` good '' and `` bad . '' these words have served as treacherous liars for eternity . these two words have worked in tandem to produce vague and bland sentences that have crippled the creativity of humanity . these two deceptively tiny words stifle real description and honest communication . look at them , just sitting there on this page , all smug and satisfied with their work . how dare they ? you serve no purpose in our world , and we must rid ourselves of your influence . we must replace these two words with the truth , with phrases that include adequate and sincere adjectives . i 'll offer you `` radiant , '' `` stupefying , '' `` awful , '' `` gut-wrenching . '' these choices create clarity and depth . `` good '' and `` bad '' only provide gray vagueness . we must demand color ! we should even use winding similes and metaphors , where appropriate . we have to do whatever we can and should to make our real sentiments known . `` good '' and `` bad '' will no longer be our go-to words that we rely on when we are too afraid or too languid to express our real thoughts . ladies and gentlemen of the jury , i implore you to deliver a verdict of guilty and send these words to their rightful fate . now imagine a world without these two words . imagine a world where real description is required , digging further into our vocabulary than just a monosyllabic effort to get away with not being honest , impactful , creative . how does my hair look ? good . what is that ? a dull attempt not to be honest ? perhaps my hair looks like a hideous mess of tangles and bald spots . yet someone does not want to be honest , and offers the quick fix `` good , '' to try and mask the truth and send me hurling into the evening with a plop of disorganized tresses . this will not do . perhaps my hair looks like an amazing glossy sculpture that frames my face perfectly , and lends an air of magic to the night . well , `` good '' just does n't cut it . i wo n't take any more of this formless , lifeless description . i will not take these lies , and neither should you . a doctor asks you how you feel . `` i feel bad . '' heresy ! the doctor , based on this paltry report , could conclude that you have brain cancer or the flu or rabies . you owe it to yourself and the possible misdiagnosis of your life to be honest about exactly how you feel . `` i feel like a herd of wombats has taken up in my chest . '' a-ha ! there we have it . an accurate description . now the doctor has some real evidence to work with in order to assist you . we have become addicted to the numbness that `` good '' and `` bad '' have created . we have become linguistic slobs , churning out `` good '' and `` bad '' wherever we are too lazy to allow our minds to communicate with creativity and specification . you look good , you sound bad , this tastes good , the weather looks bad . lie after lie , repeating this verbal gray , this sloshy mush , this fuzzy picture that reflects no real truth . replace them with grittier , exact terms that have been buried in our lexis , waiting to see daylight . no longer does the weather look good or bad , the weather looks ominous or exhilarating . nothing tastes good or bad . it tastes like pillows of sparkles or old shoe and dung . no more of sounding good or bad . you sound like lilting baby laughter or ogres marching to war . dear god , you do not look good or bad . you look like a feathery angel or a morose faun . today , you look at these two words , `` good '' and `` bad , '' examine them closely . because behind their seemingly unassuming visages reside two deceitful offerings that smother the truth . these words are liars . these words must be stopped . remove them from our language so that honesty can return to our communication . ladies and gentlemen , if i say to you that you have been a good jury , you will take the compliment , make your decision and go on about your day . but if i say to you that you are an honorable jury , and that i hope your unshakeable determination to better the vocabulary of humanity will result in finding `` good '' and `` bad '' guilty , you will recognize the ingenuity of this argument and find `` good '' and `` bad '' guilty . ( music )	how does my hair look ? good . what is that ?	the primary reason for replacing the terms good and bad in writing and speaking is ?
what would you do if you thought your country was on the path to tyranny ? if you saw one man gaining too much power , would you try to stop him ? even if that man was one of your closest friends and allies ? these were the questions haunting roman senator marcus junius brutus in 44 bce , the year julius caesar would be assassinated . opposing unchecked power was n't just a political matter for brutus ; it was a personal one . he claimed descent from lucius junius brutus , who had helped overthrow the tyrannical king known as tarquin the proud . instead of seizing power himself , the elder brutus led the people in a rousing oath to never again allow a king to rule . rome became a republic based on the principle that no one man should hold too much power . now , four and a half centuries later , this principle was threatened . julius ceasar 's rise to the powerful position of consul had been dramatic . years of military triumphs had made him the wealthiest man in rome . and after defeating his rival pompey the great in a bitter civil war , his power was at its peak . his victories and initiatives , such as distributing lands to the poor , had made him popular with the public , and many senators vied for his favor by showering him with honors . statues were built , temples were dedicated , and a whole month was renamed , still called july today . more importantly , the title of dictator , meant to grant temporary emergency powers in wartime , had been bestowed upon caesar several times in succession . and in 44 bce , he was made dictator perpetuo , dictator for a potentially unlimited term . all of this was too much for the senators who feared a return to the monarchy their ancestors had fought to abolish , as well as those whose own power and ambition were impeded by caesar 's rule . a group of conspirators calling themselves the liberators began to secretly discuss plans for assassination . leading them were the senator gaius cassius longinus and his friend and brother-in-law , brutus . joining the conspiracy was not an easy choice for brutus . even though brutus had sided with pompey in the ill-fated civil war , caesar had personally intervened to save his life , not only pardoning him but even accepting him as a close advisor and elevating him to important posts . brutus was hesitant to conspire against the man who had treated him like a son , but in the end , cassius 's insistence and brutus 's own fear of caesar 's ambitions won out . the moment they had been waiting for came on march 15 . at a senate meeting held shortly before caesar was to depart on his next military campaign , as many as 60 conspirators surrounded him , unsheathing daggers from their togas and stabbing at him from all sides . as the story goes , caesar struggled fiercely until he saw brutus . despite the famous line , `` et tu , brute ? '' written by shakespeare , we do n't know caesar 's actual dying words . some ancient sources claim he said nothing , while others record the phrase , `` and you , child ? `` , fueling speculation that brutus may have actually been caesar 's illegitimate son . but all agree that when caesar saw brutus among his attackers , he covered his face and gave up the fight , falling to the ground after being stabbed 23 times . unfortunately for brutus , he and the other conspirators had underestimated caesar 's popularity among the roman public , many of whom saw him as an effective leader , and the senate as a corrupt aristocracy . within moments of caesar 's assassination , rome was in a state of panic . most of the other senators had fled , while the assassins barricaded themselves on the capitoline hill . mark antony , caesar 's friend and co-consul , was swift to seize the upper hand , delivering a passionate speech at caesar 's funeral days later that whipped the crowd into a frenzy of grief and anger . as a result , the liberators were forced out of rome . the ensuing power vacuum led to a series of civil wars , during which brutus , facing certain defeat , took his own life . ironically , the ultimate result would be the opposite of what the conspirators had hoped to accomplish : the end of the republic and the concentration of power under the office of emperor . opinions over the assassination of caesar were divided from the start and have remained so . as for brutus himself , few historical figures have inspired such a conflicting legacy . in dante 's `` inferno , '' he was placed in the very center of hell and eternally chewed by satan himself for his crime of betrayal . but swift 's `` gulliver 's travels '' described him as one of the most virtuous and benevolent people to have lived . the interpretation of brutus as either a selfless fighter against dictatorship or an opportunistic traitor has shifted with the tides of history and politics . but even today , over 2000 years later , questions about the price of liberty , the conflict between personal loyalties and universal ideals , and unintended consequences remain more relevant than ever .	a group of conspirators calling themselves the liberators began to secretly discuss plans for assassination . leading them were the senator gaius cassius longinus and his friend and brother-in-law , brutus . joining the conspiracy was not an easy choice for brutus .	what was the name of brutus ' main co-conspirator and brother-in-law ?
so nickel is a metal which can produce allergies in some people , people get allergic to nickel . and it ’ s a metal which is found in canada and sir ludwig mond founder of the company that later becomes ici discovered a process for extracting nickel from the ore using carbon monoxide and started a huge factory on the south coast of wales . and the so-called nickel carbonyl was really quite an important industrial compound even though it was fantastically toxic . and it ’ s unusual as a metal compound because it boils at room temperature and usually one thinks of metal compounds as salts . nickel is now used quite a lot in the plating industry for plating materials , iron and steel in particular , and then often you would put chromium or something on top . used to be used for plating the inside of tins for peas and things like that . and sometimes the sulphur from inside the peas would be released by bacteria and would react to find strange black spots across the insides of the tin .	so nickel is a metal which can produce allergies in some people , people get allergic to nickel . and it ’ s a metal which is found in canada and sir ludwig mond founder of the company that later becomes ici discovered a process for extracting nickel from the ore using carbon monoxide and started a huge factory on the south coast of wales .	metallic nickel can act as a catalyst for the reaction of hydrogen gas with organic compounds that contain c=c bonds . why do you think the catalyst works better as small particles , rather than as a single large piece of nickel ?
throughout the history of mankind , three little words have sent poets to the blank page , philosophers to the agora , and seekers to the oracles : `` who am i ? '' from the ancient greek aphorism inscribed on the temple of apollo , `` know thyself , '' to the who 's rock anthem , `` who are you ? '' philosophers , psychologists , academics , scientists , artists , theologians and politicians have all tackled the subject of identity . their hypotheses are widely varied and lack significant consensus . these are smart , creative people , so what 's so hard about coming up with the right answer ? one challenge certainly lies with the complex concept of the persistence of identity . which you is who ? the person you are today ? five years ago ? who you 'll be in 50 years ? and when is `` am '' ? this week ? today ? this hour ? this second ? and which aspect of you is `` i '' ? are you your physical body ? your thoughts and feelings ? your actions ? these murky waters of abstract logic are tricky to navigate , and so it 's probably fitting that to demonstrate the complexity , the greek historian plutarch used the story of a ship . how are you `` i '' ? as the tale goes , theseus , the mythical founder king of athens , single-handedly slayed the evil minotaur at crete , then returned home on a ship . to honor this heroic feat , for 1000 years athenians painstakingly maintained his ship in the harbor , and annually reenacted his voyage . whenever a part of the ship was worn or damaged , it was replaced with an identical piece of the same material until , at some point , no original parts remained . plutarch noted the ship of theseus was an example of the philosophical paradox revolving around the persistence of identity . how can every single part of something be replaced , yet it still remains the same thing ? let 's imagine there are two ships : the ship that theseus docked in athens , ship a , and the ship sailed by the athenians 1000 years later , ship b . very simply , our question is this : does a equal b ? some would say that for 1000 years there has been only one ship of theseus , and because the changes made to it happened gradually , it never at any point in time stopped being the legendary ship . though they have absolutely no parts in common , the two ships are numerically identical , meaning one and the same , so a equals b . however , others could argue that theseus never set foot on ship b , and his presence on the ship is an essential qualitative property of the ship of theseus . it can not survive without him . so , though the two ships are numerically identical , they are not qualitatively identical . thus , a does not equal b . but what happens when we consider this twist ? what if , as each piece of the original ship was cast off , somebody collected them all , and rebuilt the entire original ship ? when it was finished , undeniably two physical ships would exist : the one that 's docked in athens , and the one in some guy 's backyard . each could lay claim to the title , `` the ship of theseus , '' but only would could actually be the real thing . so which one is it , and more importantly , what does this have to do with you ? like the ship of theseus , you are a collection of constantly changing parts : your physical body , mind , emotions , circumstances , and even your quirks , always changing , but still in an amazing and sometimes illogical way , you stay the same , too . this is one of the reasons that the question , `` who am i ? '' is so complex . and in order to answer it , like so many great minds before you , you must be willing to dive into the bottomless ocean of philosophical paradox . or maybe you could just answer , `` i am a legendary hero sailing a powerful ship on an epic journey . '' that could work , too .	though they have absolutely no parts in common , the two ships are numerically identical , meaning one and the same , so a equals b . however , others could argue that theseus never set foot on ship b , and his presence on the ship is an essential qualitative property of the ship of theseus . it can not survive without him .	when something is a paradox , it means that it seems illogical . how is the story of the ship of theseus a paradox ?
translator : andrea mcdonough reviewer : bedirhan cinar what is a cartoon really ? many of us love cartoons , most of us grew up reading them or having them read to us . the fact is , cartoons have been around a long time . there are all kinds of cartoons : strip comics , comic books , political cartoons , single-panel cartoons , graphic novels , web comics , animation , caricature , there is something for everyone . no matter the form them come in , cartoons elicit all kinds of emotions from the viewer - happiness , sadness , anger , hilarity , calm - and can transmit ideas in an instant . cartoons are a universal medium enjoyed and understood around the world and across borders . this is why they have survived so long as an art form . but how can a medium that is on the surface so simple have so much influence and at times be so meaningful ? let 's look at what a cartoon is . it starts with an idea . the idea can be verbal , written in words , or it can be visual . a visual idea is simply a picture , a drawing , a doodle . these ideas come from a variety of places . cartoonists might find the idea from observing life , reading a newspaper , trawling online . it can come from a sentence someone said or a single word heard on television . cartoonists are like sponges ; they soak up people , places , mannerisms , clothing , and behavior . sometimes they might jot them down in a little black book that they carry around with them . other times , it is just soaked up into the cartoonist 's brain only to be squeezed out later when she is sitting at her drawing table . not only does a cartoonist have to be aware of what she is seeing visually , but she has to listen to herself think . in other words , take the incoming information and select it , shape it , and then use it for a cartoon . now that you have an idea , or something you think could be good for a cartoon , it 's time to shape it . a cartoon is like a staged play . a cartoonist is playwright , director , stage designer , choreographer , and costume designer . a cartoon has characters , a set , dialogue , even if one line , and a backstory . the characters must be dressed to fit the idea , speak in a way that is natural and forwards the idea or gives the punchline . nothing should be in the cartoon that is not absolutely necessary for the advancement of the idea . the image and words have to < i > dance < /i > together in a way that makes sense . it could be a graceful dance , or an awkward dance , if that is part of the humor or idea . and then the execution . some cartoonists sketch the idea with pencil then ink it with pen using a light box . others visualize the image in their head and draw directly on the paper in pen . different kinds of pens are used : felt-tip , mechanical pen , or a crow quill . paper can be light-weight or heavy-bond . many cartoonists add gray tone , called a wash , by using black watercolor and a brush . others use a soft pencil for the tone . color is usually created by using watercolor . a finished cartoon can then be scanned and adjusted , and the caption can be added on the computer with photoshop . new technologies are emerging for the cartoonist 's use in creating her cartoon . photoshop can serve as a tool for color and image . some may draw directly on a tablet with a stylus . the choices at this stage of creation work in tandem with the idea , and often when the final caption is added , it gets adjusted yet again . but , little is left to chance , except , perhaps , some of the watercolor . all these elements function in concert with one another . it 's almost like a dance of words , ideas , and images that work together in order to make the cartoon a timeless , resilient work of art .	the fact is , cartoons have been around a long time . there are all kinds of cartoons : strip comics , comic books , political cartoons , single-panel cartoons , graphic novels , web comics , animation , caricature , there is something for everyone . no matter the form them come in , cartoons elicit all kinds of emotions from the viewer - happiness , sadness , anger , hilarity , calm - and can transmit ideas in an instant .	pick a topic ( personal , political , social ) and sketch a single panel cartoon . document your process and explain what you found to be the most difficult .
when you think of natural history museums , you probably picture exhibits filled with ancient lifeless things , like dinosaurs meteroites , and gemstones . but behind that educational exterior , which only includes about 1 % of a museum 's collection , there are hidden laboratories where scientific breakthroughs are made . beyond the unmarked doors , and on the floors the elevators wo n't take you to , you 'd find windows into amazing worlds . this maze of halls and laboratories is a scientific sanctuary that houses a seemingly endless variety of specimens . here , researchers work to unravel mysteries of evolution , cosmic origins , and the history of our planet . one museum alone may have millions of specimens . the american museum of natural history in new york city has over 32,000,000 in its collection . let 's take a look at just one of them . scientists have logged exactly where and when it was found and used various dating techniques to pinpoint when it originated . repeat that a million times over , and these plants , animals , minerals , fossils , and artifacts present windows into times and places around the world and across billions of years of history . when a research problem emerges , scientists peer through these windows and test hypotheses about the past . for example , in the 1950s , populations of predatory birds , like peregrine falcons , owls , and eagles started to mysteriously crash , to the point where a number of species , including the bald eagle , were declared endangered . fortunately , scientists in the field museum in chicago had been collecting the eggs of these predatory birds for decades . they discovered that the egg shells used to be thicker and had started to thin around the time when an insecticide called ddt started being sprayed on crops . ddt worked very well to kill insects , but when birds came and ate those heaps of dead bugs , the ddt accumulated in their bodies . it worked its way up the food chain and was absorbed by apex predator birds in such high concentrations that it thinned their eggs so that they could n't support the nesting bird 's weight . there were omelettes everywhere until scientists from the field museum in chicago , and other institutions , helped solve the mystery and save the day . america thanks you , field museum . natural history museums windows into the past have solved many other scientific mysteries . museum scientists have used their collections to sequence the neanderthal genome , discover genes that gave mammoths red fur , and even pinpoint where ancient giant sharks gave birth . there are about 900 natural history museums in the world , and every year they make new discoveries and insights into the earth 's past , present and future . museum collections even help us understand how modern threats , such as global climate change , are impacting our world . for instance , naturalists have been collecting samples for over 100 years from walden pond , famously immortalized by henry david thoreau . thanks to those naturalists , who count thoreau among their number , we know that the plants around walden pond are blooming over three weeks earlier than they did 150 years ago . because these changes have taken place gradually , one person may not have noticed them over the span of a few decades , but thanks to museum collections , we have an uninterrupted record showing how our world is changing . so the next time you 're exploring a natural history museum , remember that what you 're seeing is just one gem of a colossal scientific treasure trove . behind those walls and under your feet are windows into forgotten worlds . and who knows ? one day some future scientist may peer through one and see you .	america thanks you , field museum . natural history museums windows into the past have solved many other scientific mysteries . museum scientists have used their collections to sequence the neanderthal genome , discover genes that gave mammoths red fur , and even pinpoint where ancient giant sharks gave birth .	changes that take place gradually are difficult to observe over only a few decades . however , natural history museums can help . how ?
ralph waldo emerson is the father of american literature . in a series of strikingly original essays , written in the mid-nineteenth century , he fundamentally changed the way that america saw its cultural and artistic possibilities , and he enabled a separation from transatlantic literary traditions . `` we have listened too long ... '' , he wrote , `` ... to the courtly muses of europe . '' emerson 's abjection of cultural traditions brought about what one contemporary called : `` america 's intellectual declaration of independence . '' and he established generational conflict and transformation as commanding ideas in american literature . emerson himself hardly seemed destined to fit a revolutionary mold . he was born in 1803 , the son of a boston preacher , and was descended from a line of new england ministers that went back to the bedrock of seventeenth-century puritanism . when his father died in 1811 , his mother took in boarders to pay the rent . still , she sent her son to harvard in 1817 , and then harvard divinity school to train for the priesthood in 1825 . as a young man , emerson was strongly influenced by a remarkable aunt of his : mary moody emerson , who though self-taught , had read everything from shakespeare to the romantics and it formed a unique religious perspective based on piety nature and literature , that would resonate powerfully in the life and work of her nephew . so when emerson was ordained in 1829 , marrying the love of his life ellen tucker in the same year , he was already unsatisfied with the formal nature of new england religious orthodoxy . when ellen died of tuberculosis just two years later , he resigned from the church and soon after embarked on a trip to europe . leaving on christmas day 1832 , two crucial things happened to emerson on that tour of europe . in paris , he went to the famous `` jardin des plantes '' , a botanical and zoological garden . there he had an epiphany . writing in his journal that : `` i feel the centipede in me , the cayman , carp , eagle and fox ... ... i am moved by strange sympathies . i say continually : i will be a naturalist . `` . emerson 's insight was that nature is in us , a part of us , and not just its higher forms , but in all its grotesquerie and wildness . the second thing that happened on that tour , was that emerson met the english romantic poets : samuel taylor coleridge and william wordsworth , and found them rather ordinary , dry and conservative men . the insight that emerson drew from this , was that if great men could be so ordinary , why should not ordinary men be great ? as he would write a few years later , meek young men grow up in libraries , believing it their duty , to accept the views which cicero , locke , bacon have given . forgetful that cicero , locke and bacon were only young men in libraries when they wrote these books . emerson had found two ideas that would guide his life 's work . that man and nature are one and that everyone can recognize that they are a uniquely , significant human being . on his return to america in 1833 , emerson became a professional lecturer giving talks on natural history and literature in halls around new england . he remarried and had several children , presenting a stolid , bourgeois appearance to the world . but his inner life was full of turbulence and originality . in his 1836 essay , `` nature '' , emerson outlined the germ of a new philosophy , a key element of this , was the importance of american originality . in its opening lines , emerson wrote : `` our age is retrospective , it builds the sepulchres of the fathers . it writes biographies , histories and criticism . the foregoing generations beheld god and nature face to face ; we , through their eyes . why should not we also enjoy an original relation to the universe ? `` . america , needed to stop looking back to its european heritage and start looking about it self . no past moment was more important , than the present moment . no tradition was more important , than novelty . no generation , was better than the current generation . everything that matters is here now insisted emerson , and that here was : america . this was an extension of emerson 's ideas , about the significance of the individual that came under the heading of what he called `` self-reliance '' . everywhere emerson looked , he saw people leading lives that were based on tradition , that were limited by religious forms and social habits . no one could be themselves , emerson thought , because they were all too busy being what they were supposed to be . emerson wanted to get rid of each of these burdens : the past , religion and social forms , so that each person could find out who they truly were . as he put it : `` history is an impertinence and an injury ; our religion , we have not chosen , but society has chosen for us ... and ... ... society everywhere is in conspiracy against the manhood of every one of its members . '' we must , he argued , live from within trusting nothing but our own intuitions . for , as he concluded ... ... nothing is at last sacred but the integrity of your own mind . this leaves open a vital question : what is your nature ... ... once you 've rid yourself of history , tradition and religion ? what can be said is that it is n't necessarily self-indulgence , haterism or narcissism . rather , it 's the surrender to that force which emerson recognized back in the jardin des plantes . an obedience to nature itself . by nature , emerson seem to mean the natural world : plants , animals , rocks and sky , but what he really meant was god . emerson was a `` pantheist '' . that is , someone who believe that god exists in every part of creation , from the smallest grain of sand to the stars . but also crucially that the divine spark is in each of us . in following ourselves , we are therefore not merely being fickle or selfish , we are rather , releasing a divine will , that history , society and organized religion normally hide from us . the individual as emerson writes `` is a god in ruins '' . but we have it within us , by casting off all custom to rebuild ourselves emerson makes this pantheist connection , explicit in what are perhaps his most famous lines . `` crossing a bear common , in snow puddles at twilight under a clouded sky , without having in my thoughts any occurrence of special good fortune , i 've enjoyed a perfect exhilaration . i am glad to the brink of fear , standing on the bare ground , my head bathed by the blythe air and uplifted into infinite space , all mean egotism vanishes ... ... i become a transparent eyeball ... ... i am nothing ... ... i see all . the currents of the universal being circulate through me ... ... i am part or particle of god ! in the romantic tradition on which emerson draws , it is the sublime , great mountains , rushing torrance , dark forests , which releases the inner vision as we find ourselves in all of them . for emerson , it 's a perfectly dull walk across an ordinary common on a dark winter 's evening that brings him , to the brink of fear . emerson 's god , is in the snow puddles too . stood there on the common , he disappears , becoming nothing as the currents of god flow through him . what is left is just , a transparent eyeball . such transcendent moments are rare , but they reveal an essential connection between nature , god and man . they are one . they also give emerson a proper sense of each individual 's importance , as a part of god . transcendentalism became the name of the movement that grew up around emerson , at this time . another aspect of the epiphany that was to have a profound effect on american literature , was the emphasis on the value of the ordinary . what emerson put forward in essays like `` the american scholar '' and `` the poet '' , was that the american every day , was a proper subject for literature . this was because for emerson , the transcendentalist god is everywhere , and it 's the poet 's job to reveal this . `` there is no object ... '' , he wrote , `` ... so foul that intense light will not make it beautiful . '' `` ... even a corpse has its own beauty . '' this coming from a man who had opened his first wife 's tomb a year after her death ... ... to take a look ! the great american writers , who followed emerson , were liberated by his work to look around and write about what they saw and how they lived , transforming the everyday into a vital symbol of something higher and more elusive . henry david thoreau 's two years at walden pond , became a book that showed the cosmos reflected in the depths of the waters of a mere pond . the poet walt whitman said : `` i was simmering , simmering , simmering ... ... emerson brought me to a boil . '' emily dickinson heard a fly and could write of the other side of death . the novelist herman melville , took a whaling voyage , and made it an allegory of american imperialism and the defiance of nature . in the 20th century , the american critic harold bloom looked back at emerson 's originality and saw in it the origin of : `` the strong tradition of american poets . '' from robert frost and wallace stevens to john ashbery , emerson 's legacy to american literature and culture and indeed to the world , was one of ceaseless invention and forward momentum . as he put it : `` i unsettle all things ... ... no facts are to me sacred , none are profane ... ... i simply experiment an endless seeker with no past at my back . '' people of paul pronouncing his name if you do n't speak german it 's not at all obvious how you 're supposed to say it a safe bet is to start with a hard was a great check writer who has come to own a part of the human emotional spectrum which we can now call the casket desk and which thanks to him where	emerson 's abjection of cultural traditions brought about what one contemporary called : `` america 's intellectual declaration of independence . '' and he established generational conflict and transformation as commanding ideas in american literature . emerson himself hardly seemed destined to fit a revolutionary mold .	emerson 's work ushered in generational conflict and transformation as commanding ideas in american literature . what other aspects of american history and society are dominated by these ideas .
`` we are hurtling toward the day when climate change could be irreversible . '' `` rising sea levels already altering this nation ’ s coast . '' `` china ’ s capital is choking in its worst pollution of the year . '' `` 5 % of species will become extinct . '' `` sea levels rising , glaciers melting . '' okay . enough . i get it . it ’ s not like i don ’ t care about polar bears and melting ice caps . i ’ m a conservation scientist , so of course i care . i ’ ve dedicated my entire career to this . but over the years , one thing has become clear to me : we need to change the way we talk about climate change . this doom-and-gloom messaging just isn ’ t working ; we seem to want to tune it out . and this fear , this guilt , we know from psychology is not conducive to engagement . it 's rather the opposite . it makes people passive , because when i feel fearful or guilt-full , i will withdraw from the issue and try to think about something else that makes me feel better . and with a problem this overwhelming , it ’ s pretty easy to just turn away and kick the can down the road . somebody else can deal with it . so it ’ s no wonder that scientists and policymakers have been struggling with this issue too . so i like to say that climate change is the policy problem from hell . you almost could n't design a worse problem as a fit with our underlying psychology or the way our institutions make decisions . many americans continue to think of climate change as a distant problem : distant in time , that the impacts wo n't be felt for a generation or more ; and distant in space , that this is about polar bears or maybe some developing countries . again , it ’ s not like we don ’ t care about these things — it ’ s just such a complicated problem . but the thing is , we ’ ve faced enormous , scary climate issues before . remember the hole in the ozone layer ? as insurmountable as that seemed in the 1970s and ’ 80s , we were able to wrap our heads around that and take action . people got this very simple , easy to understand , concrete image of this protective layer around the earth , kind of like a roof , protecting us , in this case , from ultraviolet light , which by the way has the direct health consequence of potentially giving you skin cancer . okay , so now you 've got my attention . and so then they came up with this fabulous term , the “ ozone hole. ” terrible problem , great term . people also got a concrete image of how we even ended up with this problem . for decades , chlorofluorocarbons , or cfcs , were the main ingredient in a lot of products , like aerosol spray cans . then scientists discovered that cfcs were actually destroying the atmospheric ozone . people could look at their own hairspray and say , “ do i want to destroy the planet because of my hairspray ? i mean , god no. ” and so what 's interesting is that sales of hairspray and those kinds of products and underarm aerosols started dropping quite dramatically . people listened to scientists and took action . now scientists predict that the hole in the ozone layer will be healed around 2050 . that ’ s actually pretty amazing . and while stopping the use of one product is actually pretty easy , climate change caused by greenhouse gases … that ’ s much trickier . because the sources are more complicated , and for the most part , they ’ re totally invisible . right now , there is co2 pouring out of tailpipes , there is co2 pouring out of buildings , there is co2 pouring out of smokestacks , but you ca n't see it . the fundamental cause of this problem is largely invisible to most of us . i mean , if co2 was black , we would have dealt with this issue a long time ago . so co2 touches every part of our lives — our cars , the places we work , the food we eat . for now , let ’ s just focus on one thing : our energy use . how do we make that visible ? that was the initial goal of ucla ’ s engage project , one of the nation ’ s largest behavioral experiments in energy conservation . what we 're trying to do is to figure out how to frame information about electricity usage so that people save energy and conserve electricity . the idea is that electricity is relatively invisible to people . the research team outfitted part of a student housing complex with meters that tracked real-time usage of appliances and then sent them weekly reports . so you can see how much energy the stove used versus the dishwasher or the fridge . we realized , because of this project , the fridge was like the monster . so lucky for them , their landlord upgraded their fridge to an energy-efficient one . they also learned other energy-saving tips , like unplugging their dishwasher when not in use and air-drying their clothes during the summer months . and researchers , in turn , discovered where people were willing to cut back . the engage project wanted to know what types of messaging could motivate people to change their behavior . we wanted to see over time over a year and with repeated messages , how do people , behave ? how does that impact the consumer behavior ? and what we found is that it 's very different . some households were sent personalized emails with their energy bill about how they could save money ; others learned how their energy usage impacted the environment and children ’ s health . those who received messages about saving money did nothing . it was totally ineffective because electricity is relatively cheap . but emails sent that linked the amount of pollutants produced to rates of childhood asthma and cancer — well , those led to an 8 % drop in energy use , and 19 % in households with kids . now , in a separate study , researchers brought social competition into the mix . first , they hung posters around a dorm building to publicly showcase how students were really doing : red dots for energy wasters , green for those doing a good job , and a shiny gold star for those going above and beyond . this social pressure approach led to a 20 % reduction in energy use . this strategy was also used at paulina ’ s complex , and it definitely brought out her competitive streak . for me , the competition was what motivated me , because seeing your apartment number and telling you that you are doing at the average , but you are not the best , was like , why ? i ’ m doing everything you are telling me to do . i always wanted the gold star , because it was like , “ oh , my god , i want to be like the less consumption of energy in the whole building. ” and psychology studies have proved this . we are social creatures , and as individualistic as we can be , turns out we do care about how we compare to others . and yes , we do like to be the best . some people don ’ t want to say , oh , i 'm like the average . no , my usage is different and i want to be able to act on it . and people can act on it because with these meters , they can now see their exact impact . a company called opower is playing with this idea of social competition . they work with over 100 utility companies to provide personalized energy reports to millions of customers around the world . now consumers can not only see their energy use but how it compares to their neighbors ’ . like the ucla study found , this subtle social pressure encourages consumers to save energy . it ’ s been so effective that in 2016 , opower was able to generate the equivalent of two terawatt-hours of electricity savings . that ’ s enough to power every home in miami for more than a year . and they ’ re not alone . even large companies are tapping into behavioral science to move the dial . virgin atlantic airways gave a select group of pilots feedback on their fuel use . over the course of a year , they collectively saved over 6,800 tons of fuel by making some simple changes : adjusting their altitudes , routes , and speed reduced their carbon dioxide emissions by over 21,000 tons . these behavioral “ nudges ” do seem to be advancing how we as a society deal with some pretty complicated climate change issues , but it turns out we ’ re just getting started . there is no “ quick fix. ” we need people changing their companies , changing their business models , changing the products and services they provide . this is about broader-scale change . and part of this change includes embracing what makes us human . that it can ’ t just be a guilt trip about dying polar bears or driving around in gas guzzlers . we need to talk about our wins , as well — like how we ’ re making progress , really being aware of our energy use , and taking advantage of that competitive spirit we all have in order to really move us from a state of apathy to action . global warming is by far the biggest issue of our time . climate lab is a new series from vox and the university of california , and we ’ ll be exploring some surprising ways we can tackle this problem . if you want to learn more , head to climate.universityofcalifornia.edu .	people listened to scientists and took action . now scientists predict that the hole in the ozone layer will be healed around 2050 . that ’ s actually pretty amazing .	when do scientists predict the hole in the ozone layer will be healed ?
statistics are persuasive . so much so that people , organizations , and whole countries base some of their most important decisions on organized data . but there 's a problem with that . any set of statistics might have something lurking inside it , something that can turn the results completely upside down . for example , imagine you need to choose between two hospitals for an elderly relative 's surgery . out of each hospital 's last 1000 patient 's , 900 survived at hospital a , while only 800 survived at hospital b . so it looks like hospital a is the better choice . but before you make your decision , remember that not all patients arrive at the hospital with the same level of health . and if we divide each hospital 's last 1000 patients into those who arrived in good health and those who arrived in poor health , the picture starts to look very different . hospital a had only 100 patients who arrived in poor health , of which 30 survived . but hospital b had 400 , and they were able to save 210 . so hospital b is the better choice for patients who arrive at hospital in poor health , with a survival rate of 52.5 % . and what if your relative 's health is good when she arrives at the hospital ? strangely enough , hospital b is still the better choice , with a survival rate of over 98 % . so how can hospital a have a better overall survival rate if hospital b has better survival rates for patients in each of the two groups ? what we 've stumbled upon is a case of simpson 's paradox , where the same set of data can appear to show opposite trends depending on how it 's grouped . this often occurs when aggregated data hides a conditional variable , sometimes known as a lurking variable , which is a hidden additional factor that significantly influences results . here , the hidden factor is the relative proportion of patients who arrive in good or poor health . simpson 's paradox is n't just a hypothetical scenario . it pops up from time to time in the real world , sometimes in important contexts . one study in the uk appeared to show that smokers had a higher survival rate than nonsmokers over a twenty-year time period . that is , until dividing the participants by age group showed that the nonsmokers were significantly older on average , and thus , more likely to die during the trial period , precisely because they were living longer in general . here , the age groups are the lurking variable , and are vital to correctly interpret the data . in another example , an analysis of florida 's death penalty cases seemed to reveal no racial disparity in sentencing between black and white defendants convicted of murder . but dividing the cases by the race of the victim told a different story . in either situation , black defendants were more likely to be sentenced to death . the slightly higher overall sentencing rate for white defendants was due to the fact that cases with white victims were more likely to elicit a death sentence than cases where the victim was black , and most murders occurred between people of the same race . so how do we avoid falling for the paradox ? unfortunately , there 's no one-size-fits-all answer . data can be grouped and divided in any number of ways , and overall numbers may sometimes give a more accurate picture than data divided into misleading or arbitrary categories . all we can do is carefully study the actual situations the statistics describe and consider whether lurking variables may be present . otherwise , we leave ourselves vulnerable to those who would use data to manipulate others and promote their own agendas .	it pops up from time to time in the real world , sometimes in important contexts . one study in the uk appeared to show that smokers had a higher survival rate than nonsmokers over a twenty-year time period . that is , until dividing the participants by age group showed that the nonsmokers were significantly older on average , and thus , more likely to die during the trial period , precisely because they were living longer in general .	what was the important factor to consider in the uk study that analyzed smokers and non smokers ?
what 's that sound ? depending on whom you ask , the crackle of popping joints is either the sound of sweet relief or the noxious tones of a stomach-turning habit . really , though . what 's that sound ? i mean , why does bending your joints in a certain way make them pop like that ? scientists have offered several explanations , including rapidly stretching ligaments , and in severe cases , actual bones grinding against each other . but the most common explanation for why your stretched-out joints sound like bubbles popping is that , well , there are bubbles in there . the joints in your fingers are the easiest ones to crack , but many people also crack the joints between vertebrae in their neck and back , and even their hips , wrists , shoulders and so on . all these joints are synovial joints , and they 're the most flexible ones in your body . the space between the two bones is filled with a viscous liquid , synovial fluid , which contains long , lubricating molecules , like hyaluronic acid and lubricin . synovial fluid is more or less the texture of egg yolk and its primary purpose is to cushion the bones and help them glide past each other . it also contains phagocytic cells that help clean up any bone or cartilage debris that ends up in the joint . but the reason it 's important for knuckle cracking is that , like other fluids in your body , it contains lots of dissolved gas molecules . knuckle-crackers know that to get that satisfying pop , you stretch the joint farther than it normally goes by bending your fingers backwards , for example . when you do that , the bones move away from each other . the space between bones gets bigger , but the amount of synovial fluid stays constant . that creates a low-pressure zone that pulls dissolved gases out of the synovial fluid , just like the carbon dioxide that fizzes out of soda when you twist open the cap . inside the joint , the escaping gases form a bubble with a pop . but the bubble does n't last long . the surrounding fluid presses on it until it finally collapses . the bubble 's gases scatter throughout the synovial cavity and slowly dissolve back into the fluid over the course of about twenty minutes , which is why it can take a while before you can pop the same joint again . some scientists think there may actually be two pops . one when the bubble forms , and another when it bursts . popping a joint temporarily enlarges it , which may be why dedicated knuckle- , neck- and back-crackers say the habit makes their joints feel looser and more flexible . but you may have heard from a concerned relative or annoyed officemate that cracking your joints will give you arthritis . a doctor named donald unger heard this , too . so , determined to disprove his mother 's warnings , he cracked the knuckles of his left hand repeatedly for 50 years , while the right-hand knuckles went unpopped . 36,500 cracks later , both hands were arthritis-free . for this selfless act of devotion to science , dr. unger received an ig nobel prize , a parody of the nobel prize that recognizes wacky , but weirdly fascinating , scientific accomplishments . unger wrote that his results should prompt investigation into other parental beliefs , like the importance of eating spinach . the jury 's still out on that one . as for knuckle-cracking , one study suggests that all that joint stretching and bubble bursting can cause your hands to swell and weaken your grip . but the biggest proven danger seems to be annoying those around you .	that creates a low-pressure zone that pulls dissolved gases out of the synovial fluid , just like the carbon dioxide that fizzes out of soda when you twist open the cap . inside the joint , the escaping gases form a bubble with a pop . but the bubble does n't last long .	what type of joint is most commonly popped ?
figs are one of my favorite foods . they 're sweet and floral , and there 's something about the texture that i find so delightful—the outside is soft , but the seeds in the middle give you this totally satisfying crunch . but it turns out that many species of figs contain the bodies of dead wasps . i 'm anna and this is gross science . figs are n't exactly your typical fruit . you can think of them as packages that contain all of the fig tree ’ s flowers within them . but if the flowers are trapped inside the fig how do they get pollinated ? well , that 's where fig wasps come in . in most species , pregnant female fig wasps carrying pollen are attracted to young figs . they enter through a tiny opening at the fig ’ s bottom that ’ s highly selective—it usually only lets in the exact species of wasps that pollinate it . but , even the pollinators have a hard time getting in . most lose their wings and antennae in the process . the wasp ’ s goal is to find a home for her babies . and the perfect home is inside the fig ’ s female flowers—those are the ones that would produce seeds if they were fertilized . so , the mama wasp drops a fertilized egg inside as many of the female flowers as she can—sometimes , up to a few hundred . but she ca n't get to all of them . along the way , she winds up fertilizing the rest of the flowers with the fig pollen she 's carrying , and those flowers begin developing seeds . once the wasp is finished laying eggs , she usually dies inside the fig . each baby wasp begins to grow , encased in a protective structure that the plant forms called a gall . the male wasps mature first . when they emerge , they find the galls of the female wasps , many of whom are their sisters , poke inside , and impregnate them before they 've even hatched ! then , the males die inside the fig , but not before boring tiny holes through the fig ’ s skin . when the females do emerge , the fig has just started producing pollen . the female wasps pick up some of that pollen before making their way through the holes their brothers drilled , and go off to find a new fig to start the cycle again . but the story 's not over . at this point , our fig ’ s seeds are finally mature and ready to be planted . and that happens when the ripe fig is eaten by animals , which poop out the seeds , spreading fig plants far and wide . of course , humans eat figs , too . so , when you bite into a fig are you actually eating the bodies of dead wasps ? well , if you ’ re getting your figs from the supermarket , then most likely not . see , humans and figs have a really long history—we ’ ve probably been domesticating them for over 11,000 years . so , while there are over 750 species in the world , most of the figs we eat are a species called the “ common fig , ” which humans have had a huge hand in creating . in fact , some common figs are seedless and don ’ t require pollination at all . other varieties of common fig do need to be pollinated , but have separate male and female trees , and we only eat fruits from the female ones . i ’ ll put a link in the description to a great explanation of how common fig pollination happens , but long story short , female wasps can only manage to lay eggs in the the figs from male trees , not female ones . but they can ’ t tell the difference between the two types of trees . so , if a wasp does enter a female fruit , she ’ ll pollinate it , and either manage to escape or die inside the fig . and then that fig might make it to your table . frankly , one wasp here and there isn ’ t enough to deter me from eating these things . but if you 're still feeling squeamish , just think about it this way : by eating that fig , you 're benefitting from a complex and in my view , beautiful partnership—or , what ’ s called a “ mutualism ” — between two very different species . one that ’ s been delicately crafted by around 90 million years of evolution . and that certainly whets my appetite—at least for curiosity , if not for dinner . mmmm ! but also ew .	and that happens when the ripe fig is eaten by animals , which poop out the seeds , spreading fig plants far and wide . of course , humans eat figs , too . so , when you bite into a fig are you actually eating the bodies of dead wasps ?	for how long have humans been cultivating figs ?
in 1977 , the physicist edward purcell calculated that if you push a bacteria and then let go , it will stop in about a millionth of a second . in that time , it will have traveled less than the width of a single atom . the same holds true for a sperm and many other microbes . it all has to do with being really small . microscopic creatures inhabit a world alien to us , where making it through an inch of water is an incredible endeavor . but why does size matter so much for a swimmer ? what makes the world of a sperm so fundamentally different from that of a sperm whale ? to find out , we need to dive into the physics of fluids . here 's a way to think about it . imagine you are swimming in a pool . it 's you and a whole bunch of water molecules . water molecules outnumber you a thousand trillion trillion to one . so , pushing past them with your gigantic body is easy , but if you were really small , say you were about the size of a water molecule , all of a sudden , it 's like you 're swimming in a pool of people . rather than simply swishing by all the teeny , tiny molecules , now every single water molecule is like another person you have to push past to get anywhere . in 1883 , the physicist osborne reynolds figured out that there is one simple number that can predict how a fluid will behave . it 's called the reynolds number , and it depends on simple properties like the size of the swimmer , its speed , the density of the fluid , and the stickiness , or the viscosity , of the fluid . what this means is that creatures of very different sizes inhabit vastly different worlds . for example , because of its huge size , a sperm whale inhabits the large reynolds number world . if it flaps its tail once , it can coast ahead for an incredible distance . meanwhile , sperm live in a low reynolds number world . if a sperm were to stop flapping its tail , it would n't even coast past a single atom . to imagine what it would feel like to be a sperm , you need to bring yourself down to its reynolds number . picture yourself in a tub of molasses with your arms moving about as slow as the minute hand of a clock , and you 'd have a pretty good idea of what a sperm is up against . so , how do microbes manage to get anywhere ? well , many do n't bother swimming at all . they just let the food drift to them . this is somewhat like a lazy cow that waits for the grass under its mouth to grow back . but many microbes do swim , and this is where those incredible adaptations come in . one trick they can use is to deform the shape of their paddle . by cleverly flexing their paddle to create more drag on the power stroke than on the recovery stroke , single-celled organisms like paramecia manage to inch their way through the crowd of water molecules . but there 's an even more ingenious solution arrived at by bacteria and sperm . instead of wagging their paddles back and forth , they wind them like a cork screw . just as a cork screw on a wine bottle converts winding motion into forward motion , these tiny creatures spin their helical tails to push themselves forward in a world where water feels as thick as cork . other strategies are even stranger . some bacteria take batman 's approach . they use grappling hooks to pull themselves along . they can even use this grappling hook like a sling shot and fling themselves forward . others use chemical engineering . h. pylori lives only in the slimy , acidic mucus inside our stomachs . it releases a chemical that thins out the surrounding mucus , allowing it to glide through slime . maybe it 's no surprise that these guys are also responsible for stomach ulcers . so , when you look really closely at our bodies and the world around us , you can see all sorts of tiny creatures finding clever ways to get around in a sticky situation . without these adaptations , bacteria would never find their hosts , and sperms would never make it to their eggs , which means you would never get stomach ulcers , but you would also never be born in the first place . ( pop )	microscopic creatures inhabit a world alien to us , where making it through an inch of water is an incredible endeavor . but why does size matter so much for a swimmer ? what makes the world of a sperm so fundamentally different from that of a sperm whale ?	let 's do a rough estimate . people are about 1 meter in size , and a fast swimmer can travel at about 1 meter per second . a small insect might be about 1 millimeter in size and travels at about 1 millimeter per second . how do their reynolds numbers compare ?
have you ever walked into a grocery store and wondered where all those variety of apples came from ? you might find snapdragon , pixie crunch , cosmic crisp , jazz , or ambrosia next to the more familiar red delicious and granny smith . these delightfully descriptive names belong to just a handful of the over 7,500 apple varieties in the world . this huge diversity exists largely because of humanity 's efforts to bear new fruit . fruit breeding is a way to fulfill the expectations of farmers and consumers who seek specific qualities in an apple . on the one hand , farmers may want them to be disease-resistant and to store well . on the other , consumers are swayed by appearance , taste , and novelty . so , breeders have to consider everything from how well apples grow in certain climates to their color , taste , and size . and sometimes finding the perfect fit means breeding something new . to create apples with desirable characteristics , breeders first need to find parent apples that carry those characteristics . once the parents have been selected , they have to wait until the trees bloom in the spring . the breeder takes the pollen from one bloom , called the father , and transfers it by hand to the other parent bloom , called the mother , through a process called cross-pollination . once the mother bloom turns into an apple , the seeds are collected and then planted . it takes about five years for these seeds to grow into trees that produce apples , but because of the way traits are inherited , all of the seedlings produced will have different sets of genes and characteristics . this means that to achieve a desired quality , it takes a lot of offspring , not to mention patience on the breeder 's part . when a seedling does bear fruit with the desired qualities , it 's selected for further evaluation . of the original crossed seedlings , about one in every 5,000 makes it to this prestigious stage . they 're then sent to new farms where breeders can assess how various climates and soil types affect the plant 's growth . the fruit of the seedling and its many clones must then be collected and sampled to ensure consistency . breeders study about 45 traits in an apple , like the texture and firmness of the flesh , when it ripens , how sugary its juice is , and how long it stays fresh . over several years , they weed out all the bad apples , selecting only those whose fruits are the best . these exclusive plants officially form the cultivar , or new apple variety . to ensure an exact copy of this cultivar , all apple trees must be grafted from the original seedling . branches , called scion wood , are cut from the original tree and grown to generate more scion wood . segments of these trees are then grafted onto root stalk - that 's the lower section of another tree that 's been chosen from a different cultivar for its superior roots and growing ability . finally , this fusion creates a new apple tree with the desired qualities . each new plant takes up to four years before it starts producing the fruit we eat . apple breeding may be a difficult art , but it 's accessible to all : universities , companies , and even individuals can create new cultivars . but to fully own an apple , the breeder faces a final challenge - naming the fruit . after a cultivar is patented , a breeder chooses a name for its trademark . that final step grants them long-lasting rights over the apple and its clones . that name must be completely original , and the catchier , the better , of course . with over 7,500 varieties and counting , that 's why we have apples called pink lady , sweet tango , kiku , and evercrisp . the more we work with nature 's bounty to breed new cultivars , the more creative and delectable these names will become .	segments of these trees are then grafted onto root stalk - that 's the lower section of another tree that 's been chosen from a different cultivar for its superior roots and growing ability . finally , this fusion creates a new apple tree with the desired qualities . each new plant takes up to four years before it starts producing the fruit we eat .	contrast the desired characteristics of an apple for a farmer against those of a customer . think of one more for each that is not mentioned in the lesson .
what do these animals have in common ? more than you might think . along with over 5,000 other species , they 're mammals , or members of class mammalia . all mammals are vertebrates , meaning they have backbones . but mammals are distinguished from other vertebrates by a number of shared features . that includes warm blood , body hair or fur , the ability to breathe using lungs , and nourishing their young with milk . but despite these similarities , these creatures also have many biological differences , and one of the most remarkable is how they give birth . let 's start with the most familiar , placental mammals . this group includes humans , cats , dogs , giraffes , and even the blue whale , the biggest animal on earth . its placenta , a solid disk of blood-rich tissue , attaches to the wall of the uterus to support the developing embryo . the placenta is what keeps the calf alive during pregnancy . directly connected to the mother 's blood supply , it funnels nutrients and oxygen straight into the calf 's body via the umbilical cord , and also exports its waste . placental mammals can spend far longer inside the womb than other mammals . baby blue whales , for instance , spend almost a full year inside their mother . the placenta keeps the calf alive right up until its birth , when the umbilical cord breaks and the newborn 's own respiratory , circulatory , and waste disposal systems take over . measuring about 23 feet , a newborn calf is already able to swim . it will spend the next six months drinking 225 liters of its mothers thick , fatty milk per day . meanwhile , in australia , you can find a second type of mammal - marsupials . marsupial babies are so tiny and delicate when they 're born that they must continue developing in the mother 's pouch . take the quoll , one of the world 's smallest marsupials , which weighs only 18 milligrams at birth , the equivalent of about 30 sugar grains . the kangaroo , another marsupial , gives birth to a single jelly bean-sized baby at a time . the baby crawls down the middle of the mother 's three vaginas , then must climb up to the pouch , where she spends the next 6-11 months suckling . even after the baby kangaroo leaves this warm haven , she 'll return to suckle milk . sometimes , she 's just one of three babies her mother is caring for . a female kangaroo can often simultaneously support one inside her uterus and another in her pouch . in unfavorable conditions , female kangaroos can pause their pregnancies . when that happens , she 's able to produce two different kinds of milk , one for her newborn , and one for her older joey . the word mammalia means of the breast , which is a bit of a misnomer because while kangaroos do produce milk from nipples in their pouches , they do n't actually have breasts . nor do monotremes , the third and arguably strangest example of mammalian birth . there were once hundreds of monotreme species , but there are only five left : four species of echidnas and the duck-billed platypus . the name monotreme means one hole referring to the single orifice they use for reproduction , excretion , and egg-laying . like birds , reptiles , fish , dinosaurs , and others , these species lay eggs instead of giving birth to live young . their eggs are soft-shelled , and when their babies hatch , they suckle milk from pores on their mother 's body until they 're large enough to feed themselves . despite laying eggs and other adaptations that we associate more with non-mammals , like the duck-bill platypus 's webbed feet , bill , and the venomous spur males have on their feet , they are , in fact , mammals . that 's because they share the defining characteristics of mammalia and are evolutionarily linked to the rest of the class . whether placental , marsupial , or monotreme , each of these creatures and its unique birthing methods , however bizarre , have succeeded for many millennia in bringing new life and diversity into the mammal kingdom .	nor do monotremes , the third and arguably strangest example of mammalian birth . there were once hundreds of monotreme species , but there are only five left : four species of echidnas and the duck-billed platypus . the name monotreme means one hole referring to the single orifice they use for reproduction , excretion , and egg-laying .	other than the platypus , the only other type of monotreme that lives on earth today are the :
good morning hank , it 's tuesday . so earlier this morning , i was kayaking on the white river . i came to an island that only exists when the water is low , so i had to choose which stream to follow down . i thought as i always do in these situations of robert frost 's poem , the road not taken . you know , the one that ends in , `` two roads diverged in a yellow wood , and i took the one less travelled by , and that has made all the difference . '' so i followed the road that seemed the less obvious choice . it turns out that it was the less obvious for a reason . so hank , the road not taken is an interesting poem because 1. it 's kind of responsible for the death of the person it was written for and 2. what most people conclude from the poem is the exact opposite of what robert frost intended to conclude . and also , 3. this dissonance points at something terrible about poetry i think hank . but let 's start with 1 - that dead guy . so robert frost was inspired to write this poem by the many walks he took with his friend , the english poet , edward thomas . thomas was very obsessive and indecisive person , and every time they 'd come to a fork in the road , he would n't know which one to take . you know , like how if you 're in the english countryside and if you choose the wrong path , you might get eaten by a lion . but you ca n't know that until after you 've made the choice . i assume that there 'd be lions in england , at least dandy lions . in frost 's mind , the poem was gently mocking people who obsess over the importance of tiny , little decisions , right ? but as often happens with people who are mocked too gently , edward thomas did n't get the joke and took the poem very , very seriously . and so even though edward thomas was too old to be expected to enlist , he went ahead and took the road less travelled , joining the british army to fight in wii , where upon he was promptly shot through the chest and killed . since then hank , pretty much everyone , including me , has adopted edward thomas ' interpretation of the poem despite the fact that it , you know , killed him . i think there 's just something alluring about the idea choosing the less travelled is always a good idea . it would be very helpful if there was some overarching guideline , like `` follow the path that others do n't . '' also , following the road less taken has the added advantage of making everyone feel like a non-conformist , which is nice . but of course , there are a bunch of problems . for one thing , if everyone followed the road less travelled , it quickly becomes the road more travelled . furthermore , there are many times when the road more travelled is more travelled for a reason , because for instance , the road less travelled leads to a kayak unfriendly marsh . or because there 's something kind of nice about having a spouse and two kids and a mini-van . anyways hank , i 've been thinking about this a lot because over at our podcast , dear hank and john , we 've been getting a lot of questions from listeners who are making huge life decisions , you know , should i go into the military ? which college should i attend ? should i attend college at all ? as humans , we constantly have to make all these big , big decisions , with very limited information . like hank , we are both incredibly blessed to have great marriages and great spouses , but i had no idea what i was agreeing to on my wedding day . i thought i was saying , `` i want to be in a romantic relationship with you for the rest of my life . '' i did not realize that i was also saying , `` i want to be co-ceos of a company that raises children and mows lawns and stuff . '' anyways hank , the other thing about dear hank and john is that i insist on beginning each episode with a short poem . and so in the last few weeks , we 've had a bunch of discussions about poetry - whether poetry matters , what poetry does , etc . and i think we have the road not taken as one answer about what poetry can do . because poetry is so often musical and rhythmic , it has a way of sticking in our heads , like i memorized it almost by accident . frost thought that the poem was exploring how people experience choice making rather than offering advice , but precisely because it sounds good hank , it seems like good advice . and even though i know it is n't good advice , at least not consistently , i suspect that the next time i am facing a fork in the road or fork in the river , those iambic feet will wander back into my mind . and i will once again be biased , however minutely , toward the road less travelled . i guess that 's one example of how i think poetry can really matter in the real lives of real people , hank , and why i think that poets and readers alike need to be very careful with language . after all hank , we do n't want to end up like edward thomas , but we also do n't want to end up like the poet , who at least in a roundabout way , killed him . hank , i 'll see you on friday .	and so in the last few weeks , we 've had a bunch of discussions about poetry - whether poetry matters , what poetry does , etc . and i think we have the road not taken as one answer about what poetry can do . because poetry is so often musical and rhythmic , it has a way of sticking in our heads , like i memorized it almost by accident .	how do you interpret `` the road not taken '' ?
translator : andrea mcdonough reviewer : bedirhan cinar every human being starts out the same way : two cells , one from each parent , found each other and became one . and that one cell reproduced itself , dividing , dividing and dividing until there were 10 trillion of them . do you realize there 's more cells in one person 's body than there are stars in the milky way ? but those 10 trillion cells are n't just sitting there in a big pile . that would make for a pretty boring human being ! so what is it that says a nose is a nose , and toes is toes ? what is it that says this is bone and this is brain and this is heart and this is that little thing in the back of your throat you can never remember the name of ? everything you are or ever will be made of starts as a tiny book of instructions found in each and every cell . every time your body wants to make something , it goes back to the instruction book , looks it up and puts it together . so how does one cell hold all that information ? let 's get small . i mean , really small -- smaller than the tip of a sewing needle . then we can take a journey inside a single cell to find out what makes up the book of you , your genome . the first thing we see is that the whole genome , all your dna , is contained inside its own tiny compartment , called the nucleus . if we stretched out all the dna in this one cell into a single thread , it would be over 3 feet long ! we have to make it fit in a tiny compartment that 's a million times smaller . we could just bunch it up like christmas lights , but that could get messy . we need some organization . first , the long thread of dna wraps around proteins clustered into little beads called nucleosomes , which end up looking like a long , beaded necklace . and that necklace is wrapped up in its own spiral , like an old telephone cord . and those spirals get layered on top of one another until we get a neat little shape that fits inside the nucleus . voilà ! three feet of dna squeezed into a tiny compartment . if only we could hire dna to pack our suitcases ! each tiny mass of dna is called a chromosome . the book of you would have 46 chapters , one for each chromosome . twenty-three chapters of your book came from your mom , and 23 chapters came from your dad . two of those chapters , called `` x '' and `` y , '' determine if you 're male , `` xy , '' or female , `` xx . '' put them together , and we get two almost identical but slightly different sets of 23 chapters . the tiny variations are what makes each person different . it 's estimated that all the chapters together hold about 20,000 individual instructions , called genes . written out , all those 20,000 instructions are 30 million letters long ! if someone were writing one letter per second , it would take them almost an entire year to write it once . it turns out that our genome book is much , much longer than just those 30 million letters -- almost 100 times longer ! what are all those extra pages for ? well , each page of instructions has a few pages of nonsense inserted that have to be taken out before we end up with something useful . the parts we throw out , we call introns . the instructions we keep , we call exons . we can also have hundreds of pages in between each gene . some of these excess pages were inserted by nasty little infections in our ancestors , but some of them are actually helpful . they protect the ends of each chapter from being damaged , or some help our cells find a particular thing they 're looking for , or give a cell a signal to stop making something . all in all , for every page of instructions , there 's almost 100 pages of filler . in the end , each of our books ' 46 chapters is between 48 and 250 million letters long . that 's 3.2 billion letters total ! to type all that copy , you 'd be at it for over 100 years , and the book would be over 600,000 pages long . every type of cell carries the same book , but each has a set of bookmarks that tell it exactly which pages it needs to look up . so a bone cell reads only the set of instructions it needs to become bone . your brain cells , they read the set that tells them how to become brain . if some cells suddenly decide to start reading other instructions , they can actually change from one type to another . so every little cell in your body is holding on to an amazing book , full of the instructions for life . your nose reads nose pages , your toes read toes pages . and that little thing in the back of your throat ? it 's got its own pages , too . they 're under `` uvula . ''	but those 10 trillion cells are n't just sitting there in a big pile . that would make for a pretty boring human being ! so what is it that says a nose is a nose , and toes is toes ?	how many chromosomes does the human genome contain ?
the universe is bustling with matter and energy . even in the vast apparent emptiness of intergalactic space , there 's one hydrogen atom per cubic meter . that 's not the mention a barrage of particles and electromagnetic radiation passing every which way from stars , galaxies , and into black holes . there 's even radiation left over from the big bang . so is there such thing as a total absence of everything ? this is n't just a thought experiment . empty spaces , or vacuums , are incredibly useful . inside our homes , most vacuum cleaners work by using a fan to create a low-pressure relatively empty area that sucks matter in to fill the void . but that 's far from empty . there 's still plenty of matter bouncing around . manufacturers rely on more thorough , sealed vacuums for all sorts of purposes . that includes vacuum-packed food that stays fresh longer , and the vacuums inside early light bulbs that protected filaments from degrading . these vacuums are generally created with some version of what a vacuum cleaner does using high-powered pumps that create enough suction to remove as many stray atoms as possible . but the best of these industrial processes tends to leave hundreds of millions of atoms per cubic centimeter of space . that is n't empty enough for scientists who work on experiments , like the large hadron collider , where particle beams need to circulate at close to the speed of light for up to ten hours without hitting any stray atoms . so how do they create a vacuum ? the lhc 's pipes are made of materials , like stainless steel , that do n't release any of their own molecules and are lined with a special coating to absorb stray gases . raising the temperature to 200 degrees celsius burns off any moisture , and hundreds of vacuum pumps take two weeks to trap enough gas and debris out of the pipes for the collider 's incredibly sensitive experiments . even with all this , the large hadron collider is n't a perfect vacuum . in the emptiest places , there are still about 100,000 particles per cubic centimeter . but let 's say an experiment like that could somehow get every last atom out . there 's still an unfathomably huge amount of radiation all around us that can pass right through the walls . every second , about 50 muons from cosmic rays , 10 million neutrinos coming directly from the big bang , 30 million photons from the cosmic microwave background , and 300 trillion neutrinos from the sun pass through your body . it is possible to shield vacuum chambers with substances , including water , that absorb and reflect this radiation , except for neutrinos . let 's say you 've somehow removed all of the atoms and blocked all of the radiation . is the space now totally empty ? actually , no . all space is filled with what physicists call quantum fields . what we think of as subatomic particles , electrons and photons and their relatives , are actually vibrations in a quantum fabric that extends throughout the universe . and because of a physical law called the heisenberg principle , these fields never stop oscillating , even without any particles to set off the ripples . they always have some minimum fluctuation called a vacuum fluctuation . this means they have energy , a huge amount of it . because einstein 's equations tell us that mass and energy are equivalent , the quantum fluctuations in every cubic meter of space have an energy that corresponds to a mass of about four protons . in other words , the seemingly empty space inside your vacuum would actually weigh a small amount . quantum fluctuations have existed since the earliest moments of the universe . in the moments after the big bang , as the universe expanded , they were amplified and stretched out to cosmic scales . cosmologists believe that these original quantum fluctuations were the seeds of everything we see today : galaxies and the entire large scale structure of the universe , as well as planets and solar systems . they 're also the center of one of the greatest scientific mysteries of our time because according to the current theories , the quantum fluctuations in the vacuum of space ought to have 120 orders of magnitude more energy than we observe . solving the mystery of that missing energy may entirely rewrite our understanding of physics and the universe .	there 's still an unfathomably huge amount of radiation all around us that can pass right through the walls . every second , about 50 muons from cosmic rays , 10 million neutrinos coming directly from the big bang , 30 million photons from the cosmic microwave background , and 300 trillion neutrinos from the sun pass through your body . it is possible to shield vacuum chambers with substances , including water , that absorb and reflect this radiation , except for neutrinos .	what types of particles from cosmic sources go through your body most frequently ?
translator : tom carter reviewer : bedirhan cinar when we talk , sometimes we say things directly . `` i 'm going to the store , i 'll be back in five minutes . '' other times though , we talk in a way that conjures up a small scene . `` it 's raining cats and dogs out , '' we say , or `` i was waiting for the other shoe to drop . '' metaphors are a way to talk about one thing by describing something else . that may seem roundabout , but it 's not . seeing and hearing and tasting are how we know anything first . the philosopher william james described the world of newborn infants as a `` buzzing and blooming confusion . '' abstract ideas are pale things compared to those first bees and blossoms . metaphors think with the imagination and the senses . the hot chili peppers in them explode in the mouth and the mind . they 're also precise . we do n't really stop to think about a raindrop the size of an actual cat or dog , but as soon as i do , i realize that i 'm quite certain the dog has to be a small one -- a cocker spaniel , or a dachshund -- and not a golden lab or newfoundland . i think a beagle might be about right . a metaphor is n't true or untrue in any ordinary sense . metaphors are art , not science , but they can still feel right or wrong . a metaphor that is n't good leaves you confused . you know what it means to feel like a square wheel , but not what it 's like to be tired as a whale . there 's a paradox to metaphors . they almost always say things that are n't true . if you say , `` there 's an elephant in the room , '' there is n't an actual one , looking for the peanut dish on the table . metaphors get under your skin by ghosting right past the logical mind . plus , we 're used to thinking in images . every night we dream impossible things . and when we wake up , that way of thinking 's still in us . we take off our dream shoes , and button ourselves into our lives . some metaphors include the words `` like '' or `` as . '' `` sweet as honey , '' `` strong as a tree . '' those are called similes . a simile is a metaphor that admits it 's making a comparison . similes tend to make you think . metaphors let you feel things directly . take shakespeare 's famous metaphor , `` all the world 's a stage . '' `` the world is like a stage '' just seems thinner , and more boring . metaphors can also live in verbs . emily dickinson begins a poem , `` i saw no way -- the heavens were stitched -- '' and we know instantly what it would feel like if the sky were a fabric sewn shut . they can live in adjectives , too . `` still waters run deep , '' we say of someone quiet and thoughtful . and the deep matters as much as the stillness and the water do . one of the clearest places to find good metaphors is in poems . take this haiku by the 18th-century japanese poet issa . `` on a branch floating downriver , a cricket singing . '' the first way to meet a metaphor is just to see the world through its eyes : an insect sings from a branch passing by in the middle of the river . even as you see that though , some part of you recognizes in the image a small portrait of what it 's like to live in this world of change and time , our human fate is to vanish , as surely as that small cricket will , and still , we do what it does . we live , we sing . sometimes a poem takes a metaphor and extends it , building on one idea in many ways . here 's the beginning of langston hughes ' famous poem `` mother to son . '' `` well , son , i 'll tell you . life for me ai n't been no crystal stair . it 's had tacks in it , and splinters , and boards torn up , and places with no carpet on the floor . '' langston hughes is making a metaphor that compares a hard life to a wrecked house you still have to live in . those splinters and tacks feel real , they hurt your own feet and your own heart , but the mother is describing her life here , not her actual house . and hunger , and cold , exhausting work and poverty are what 's also inside those splinters . metaphors are n't always about our human lives and feelings . the chicago poet carl sandburg wrote , `` the fog comes on little cat feet . it sits looking over harbor and city on silent haunches , and then moves on . '' the comparison here is simple . fog is being described as a cat . but a good metaphor is n't a puzzle , or a way to convey hidden meanings , it 's a way to let you feel and know something differently . no one who 's heard this poem forgets it . you see fog , and there 's a small grey cat nearby . metaphors give words a way to go beyond their own meaning . they 're handles on the door of what we can know , and of what we can imagine . each door leads to some new house , and some new world that only that one handle can open . what 's amazing is this : by making a handle , you can make a world .	those are called similes . a simile is a metaphor that admits it 's making a comparison . similes tend to make you think .	a simile is
you probably do n't need to be told how important your brain is . after all , every single thing you experience , your thoughts and your actions , your perceptions and your memories are processed here in your body 's control center . but if this already seems like a lot for a single organ to handle , it 's actually only a small part of what the brain does . most of its activities are ones you 'd never be aware of , unless they suddenly stopped . the brain is made up of billions of neurons , and trillions of connections . neurons can be activated by specific stimuli or thoughts , but they are also often spontaneously active . some fire cyclically in a set pattern . others fire rapidly in short bursts before switching off , or remain quiet for long periods until thousands of inputs from other neurons line up in just the right way . on a large scale , this results in elaborate rhythms of internally generated brain activity , humming quietly in the background whether we 're awake , asleep , or trying not to think about anything at all . and these spontaneously occurring brain functions form the foundation upon which all other brain functions rely . the most crucial of these automatically occurring activities are the ones that keep us alive . for example , while you 've been paying attention to this video spontaneous activity in your brain has been maintaining your breathing at 12 to 16 breaths a minute , making sure that you do n't suffocate . without any conscious effort , signals from parts of your brainstem are sent through the spinal cord to the muscles that inflate your lungs , making them expand and contract , whether or not you 're paying attention . the neuronal circuits underlying such rhythmic spontaneous activity are called central pattern generators , and control many simple repetitive behaviors , like breathing , walking , and swallowing . ongoing neural activity also underlies our sensory perception . it may seem that the neurons in your retina that translate light into neural signals would remain quiet in the dark , but in fact , the retinal ganglion cells that communicate with the brain are always active . and the signals they send are increases and decreases in the rate of activity , rather than separate bursts . so at every level , our nervous system is teeming with spontaneous activity that helps it interpret and respond to any signals it might receive . and our brain 's autopilot is n't just limited to our basic biological functions . have you ever been on the way home , started thinking about what 's for dinner , and then realized you do n't remember walking for the past five minutes ? while we do n't understand all the details , we do know that the ongoing activity in multiple parts of your brain is somehow able to coordinate what is actually a complex task involving both cognitive and motor functions , guiding you down the right path and moving your legs while you 're getting dinner figured out . but perhaps the most interesting thing about spontaneous brain function is its involvement in one of the most mysterious and poorly understood phenomena of our bodies : sleep . you may shut down and become inactive at night , but your brain does n't . while you sleep , ongoing spontaneous activity gradually becomes more and more synchronized , eventually developing into large , rhythmic neural oscillations that envelop your brain . this transition to the more organized rhythms of sleep starts with small clusters of neurons tucked in the hypothalamus . despite their small number , these neurons have a huge effect in turning off brainstem regions that normally keep you awake and alert , letting other parts , like the cortex and thalamus , slowly slip into their own default rhythms . the deeper we fall into sleep , the slower and more synchronized this rhythm becomes , with the deepest stages dominated by large amplitude , low frequency delta waves . but surprisingly , in the middle of this slow wave sleep , the brain 's synchronized spontaneous activity repeatedly transitions into the sort of varied bursts that occur when we 're wide awake . this is the sleep stage known as rem sleep , where our eyes move rapidly back and forth as we dream . neuroscientists are still trying to answer many fundamental questions about sleep , such as its role in rejuvenating cognitive capacity , cellular homeostasis , and strengthening memory . and more broadly , they are exploring how it is that brain can accomplish such important and complex tasks , such as driving , or even breathing , without our awareness . but for now , until we are better able to understand the inner workings of their spontaneous functioning , we need to give our brains credit for being much smarter than we ourselves are .	on a large scale , this results in elaborate rhythms of internally generated brain activity , humming quietly in the background whether we 're awake , asleep , or trying not to think about anything at all . and these spontaneously occurring brain functions form the foundation upon which all other brain functions rely . the most crucial of these automatically occurring activities are the ones that keep us alive .	fast-forward a few hundred years into the future , where you are a student in a neuroscience lab . your research project is to make a conscious , fully aware robot that is as intelligent and flexible as a human ( or better ) . in the design of your robot , would you include spontaneous , automatic functions that the “ conscious ” part of the robot couldn ’ t control ? what sorts of automatic functions would you include ?
what is at the center of the universe ? it 's an essential question that humans have been wondering about for centuries . but the journey toward an answer has been a strange one . if you wanted to know the answer to this question in third century b.c.e . greece , you might look up at the night sky and trust what you see . that 's what aristotle , the guy to ask back then , did . he thought that since we 're on earth , looking up , it must be the center , right ? for him , the sphere of the world was made up of four elements : earth , water , air , and fire . these elements shifted around a nested set of solid crystalline spheres . each of the wandering stars , the planets , had their own crystal sphere . the rest of the universe and all of its stars were on the last crystal sphere . if you watch the sky change over time , you could see that this idea worked fine at explaining the motion you saw . for centuries , this was central to how europe and the islamic world saw the universe . but in 1543 , a guy named copernicus proposed a different model . he believed that the sun was at the center of the universe . this radically new idea was hard for a lot of people to accept . after all , aristotle 's ideas made sense with what they could see , and they were pretty flattering to humans . but a series of subsequent discoveries made the sun-centric model hard to ignore . first , johannes kepler pointed out that orbits are n't perfect circles or spheres . then , galileo 's telescope caught jupiter 's moons orbiting around jupiter , totally ignoring earth . and then , newton proposed the theory of universal gravitation , demonstrating that all objects are pulling on each other . eventually , we had to let go of the idea that we were at the center of the universe . shortly after copernicus , in the 1580s , an italian friar , giordano bruno , suggested the stars were suns that likely had their own planets and that the universe was infinite . this idea did n't go over well . bruno was burned at the stake for his radical suggestion . centuries later , the philosopher rene descartes proposed that the universe was a series of whirlpools , which he called vortices , and that each star was at the center of a whirlpool . in time , we realized there were far more stars than aristotle ever dreamed . as astronomers like william herschel got more and more advanced telescopes , it became clear that our sun is actually one of many stars inside the milky way . and those smudges we see in the night sky ? they 're other galaxies , just as vast as our milky way home . maybe we 're farther from the center than we ever realized . in the 1920s , astronomers studying the nebuli wanted to figure out how they were moving . based on the doppler effect , they expected to see blue shift for objects moving toward us , and red shift for ones moving away . but all they saw was a red shift . everything was moving away from us , fast . this observation is one of the pieces of evidence for what we now call the big bang theory . according to this theory , all matter in the universe was once a singular , infinitely dense particle . in a sense , our piece of the universe was once at the center . but this theory eliminates the whole idea of a center since there ca n't be a center to an infinite universe . the big bang was n't just an explosion in space ; it was an explosion of space . what each new discovery proves is that while our observations are limited , our ability to speculate and dream of what 's out there is n't . what we think we know today can change tomorrow . as with many of the thinkers we just met , sometimes our wildest guesses lead to wonderful and humbling answers and propel us toward even more perplexing questions .	in the 1920s , astronomers studying the nebuli wanted to figure out how they were moving . based on the doppler effect , they expected to see blue shift for objects moving toward us , and red shift for ones moving away . but all they saw was a red shift .	which of the following is not true about the doppler effect ?
translator : andrea mcdonough reviewer : bedirhan cinar tap dance : one of america 's major contributions to the world of percussive dance , born out of the melding of african and european dance traditions . there 's so many variations within tap dance , as many approaches as there have been tap dancers . and there have been a lot ! since its birth , over 125 years ago , tap dance has grown up in the world of american popular entertainment . from minstral shows and vaudeville , to night clubs , musical theater , and movie musicals , tap dance has held a featured role . and your approach depends on when in the history 's lineage you decide to connect . the landscape of american entertainment shifted in the 1950s and 60s . big bands became cost-prohibitive , rock and roll was becoming a popular music , and american musical theater moved towards a format incorporating ballet with narrative rather than the extension of variety shows that it had been in the past . all these factors pushed tap dancing to the fringes of the entertainment world . tap dance still existed ; there were dancers , but it was outside of the popular discourse . there were fewer and fewer places to dance and very little need for new tap dancers , so those who have been dancing in the 20s , 30s , and 40s , really had no one to pass along the art form to . in the 1970s , a multifaceted resurgence began . modern dancers became interested in the older tap dancers , drawing them out of retirement to teach . grassroots-organized tap festivals began to spring up , featuring the older tap dancers teaching the technique and the history of the craft . older dancers also came out of retirement to perform with groups such as the copasetics and the original hoofers , traveling the world . even broadway regained interest in the form , with gregory hines becoming a public figure for tap dance on the stage and in feature films . since then , the resurgence has spawned a more popular interest , with savion glover at the nexus of the crowd . considered the quintessential tap dancer , glover presents the form as a pure musician . since the 1990s , and thanks in a large part to the work of savion glover , we 've seen a rise in young people 's interest in tap dance . i 'm part of that generation . today , as we begin to rediscover the craft , we continue to look back and take examples of what tap dance was from past generations , at the same time , discovering our own unique approaches . there is so much freedom today . we can take what exists and apply past examples within our own unique context - today 's perspective on tap dance . it all really boils down to two pieces of metal on a leather-soled shoe , the wood to dance on , an audience to watch and listen , and something to say . it 's the balancing of these elements that is a tap dancer 's craft work .	from minstral shows and vaudeville , to night clubs , musical theater , and movie musicals , tap dance has held a featured role . and your approach depends on when in the history 's lineage you decide to connect . the landscape of american entertainment shifted in the 1950s and 60s . big bands became cost-prohibitive , rock and roll was becoming a popular music , and american musical theater moved towards a format incorporating ballet with narrative rather than the extension of variety shows that it had been in the past .	what 's another uniquely `` american '' art form ? briefly explain it 's history .
you might have seen this symbol before , whether it 's as a temporary tattoo or at a chinese temple . it 's called the yin-yang symbol . it comes from taoism , a religion born in china and it has far more meaning than you probably realize . the yin is the dark swirl , and the yang is the light one , and each side has a dot of the opposite color , which gives a clue to the meaning of yin and yang . everything contains the seed of its opposite . darth vadar has the seed of goodness , and luke has the potential to follow his father to the dark side . like luke and his father , yin and yang are not total opposites , they are relative to each other . taoists believe that the universe is made up of energies , vibrations , and matter , which behave differently in different contexts . something can be yin or yang depending on , well , depending on lots of things . so , while wheat that 's growing is yang , when it 's being reaped , it 's yin . a wave 's crest is yang , and the trough is yin . villages on the sunny side of a valley in china have names like liuyang or shiyang , but on the shady side , for example , of the yangtze river valley , there 's jiangyin . the brake is yin to the gas pedal 's yang . an eggshell is yang , the egg inside is yin . you think you 're getting it ? yang is harder , stronger , brighter , and faster , but one can turn into the other or are two sides of the same coin . the sunbeams are yang in comparison to the shadows . the pitch is yang , the catch is yin . the yang starts an action , and the yin receives it , completes it . yin is the inside space of a cup ; it would n't be a cup without it . yang is the cup . the coffee 's heat , however , is yang , and its blackness is yin . yang goes berserk sometimes , but there 's some very powerful yins , too , if they do n't quite go berserk . yin is the darker swirl , the female , but there is a white dot in it . and yang is the lighter , the male , but it has a black dot . water flowing calmly in a river is yin , but when it goes over the waterfall , it 's very yang . toothpicks are yin compared with a telephone pole . the back of a person is more yin than the front . the top of a person is the yang end . taoism teaches that there is a power in the universe . it 's higher , deeper , and truer than any other force . they call it the tao . it means the way . like the force in star wars , the tao has two sides . unlike other religions where the higher power is all good , and perhaps has an all-evil rival , taoism teaches that we need to learn from both yin and yang . and unlike religions with gods that are personal , the higher power in taoism is not . taoists believe that living in harmony with the way , a person will not have to fight against the universe 's natural flow . so , for example , listen more , argue less . be ready to back up or undo something , and you will make even faster progress . do n't worry about being the best , be who you are . live simply . complications take you away from the tao . `` the wise person is flexible , '' taoists say . learning to use the tao is what taoism is all about , and that 's why you should know your yin from your yang .	unlike other religions where the higher power is all good , and perhaps has an all-evil rival , taoism teaches that we need to learn from both yin and yang . and unlike religions with gods that are personal , the higher power in taoism is not . taoists believe that living in harmony with the way , a person will not have to fight against the universe 's natural flow .	in daoism , the higher power is not a god , but
slavery , the treatment of human beings as property , deprived of personal rights , has occurred in many forms throughout the world . but one institution stands out for both its global scale and its lasting legacy . the atlantic slave trade , occurring from the late 15th to the mid 19th century and spanning three continents , forcibly brought more than 10 million africans to the americas . the impact it would leave affected not only these slaves and their descendants , but the economies and histories of large parts of the world . there had been centuries of contact between europe and africa via the mediterranean . but the atlantic slave trade began in the late 1400s with portuguese colonies in west africa , and spanish settlement of the americas shortly after . the crops grown in the new colonies , sugar cane , tobacco , and cotton , were labor intensive , and there were not enough settlers or indentured servants to cultivate all the new land . american natives were enslaved , but many died from new diseases , while others effectively resisted . and so to meet the massive demand for labor , the europeans looked to africa . african slavery had existed for centuries in various forms . some slaves were indentured servants , with a limited term and the chance to buy one 's freedom . others were more like european serfs . in some societies , slaves could be part of a master 's family , own land , and even rise to positions of power . but when white captains came offering manufactured goods , weapons , and rum for slaves , african kings and merchants had little reason to hesitate . they viewed the people they sold not as fellow africans but criminals , debtors , or prisoners of war from rival tribes . by selling them , kings enriched their own realms , and strengthened them against neighboring enemies . african kingdoms prospered from the slave trade , but meeting the european 's massive demand created intense competition . slavery replaced other criminal sentences , and capturing slaves became a motivation for war , rather than its result . to defend themselves from slave raids , neighboring kingdoms needed european firearms , which they also bought with slaves . the slave trade had become an arms race , altering societies and economies across the continent . as for the slaves themselves , they faced unimaginable brutality . after being marched to slave forts on the coast , shaved to prevent lice , and branded , they were loaded onto ships bound for the americas . about 20 % of them would never see land again . most captains of the day were tight packers , cramming as many men as possible below deck . while the lack of sanitation caused many to die of disease , and others were thrown overboard for being sick , or as discipline , the captain 's ensured their profits by cutting off slave 's ears as proof of purchase . some captives took matters into their own hands . many inland africans had never seen whites before , and thought them to be cannibals , constantly taking people away and returning for more . afraid of being eaten , or just to avoid further suffering , they committed suicide or starved themselves , believing that in death , their souls would return home . those who survived were completley dehumanized , treated as mere cargo . women and children were kept above deck and abused by the crew , while the men were made to perform dances in order to keep them exercised and curb rebellion . what happened to those africans who reached the new world and how the legacy of slavery still affects their descendants today is fairly well known . but what is not often discussed is the effect that the atlantic slave trade had on africa 's future . not only did the continent lose tens of millions of its able-bodied population , but because most of the slaves taken were men , the long-term demographic effect was even greater . when the slave trade was finally outlawed in the americas and europe , the african kingdoms whose economies it had come to dominate collapsed , leaving them open to conquest and colonization . and the increased competition and influx of european weapons fueled warfare and instability that continues to this day . the atlantic slave trade also contributed to the development of racist ideology . most african slavery had no deeper reason than legal punishment or intertribal warfare , but the europeans who preached a universal religion , and who had long ago outlawed enslaving fellow christians , needed justification for a practice so obviously at odds with their ideals of equality . so they claimed that africans were biologically inferior and destined to be slaves , making great efforts to justify this theory . thus , slavery in europe and the americas acquired a racial basis , making it impossible for slaves and their future descendants to attain equal status in society . in all of these ways , the atlantic slave trade was an injustice on a massive scale whose impact has continued long after its abolition .	and the increased competition and influx of european weapons fueled warfare and instability that continues to this day . the atlantic slave trade also contributed to the development of racist ideology . most african slavery had no deeper reason than legal punishment or intertribal warfare , but the europeans who preached a universal religion , and who had long ago outlawed enslaving fellow christians , needed justification for a practice so obviously at odds with their ideals of equality .	how did the atlantic slave trade contribute to a racist ideology that continues to this day ?