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Tarski's Truth Definitions
In 1933 the Polish logician Alfred Tarski published a paper in which he discussed the criteria that a definition of 'true sentence' should meet, and gave examples of several such definitions for particular formal languages. In 1956 he and his colleague Robert Vaught published a revision of one of the 1933 truth definitions, to serve as a truth definition for model-theoretic languages. This entry will simply review the definitions and make no attempt to explore the implications of Tarski's work for semantics (natural language or programming languages) or for the philosophical study of truth. (For those implications, see the entries on truth and Alfred Tarski.)
- 1. The 1933 programme and the semantic conception
- 2. Some kinds of truth definition on the 1933 pattern
- 3. The 1956 definition and its offspring
- Bibliography
- Academic Tools
- Other Internet Resources
- Related Entries
1. The 1933 programme and the semantic conception
In the late 1920s Alfred Tarski embarked on a project to give rigorous definitions for notions useful in scientific methodology. In 1933 he published (in Polish) his analysis of the notion of a true sentence. This long paper undertook two tasks: first to say what should count as a satisfactory definition of 'true sentence' for a given formal language, and second to show that there do exist satisfactory definitions of 'true sentence' for a range of formal languages. We begin with the first task; Section 2 will consider the second.
We say that a language is fully interpreted if all its sentences have meanings that make them either true or false. All the languages that Tarski considered in the 1933 paper were fully interpreted, with one exception described in Section 2.2 below. This was the main difference between the 1933 definition and the later model-theoretic definition of 1956, which we shall examine in Section 3.
Tarski described several conditions that a satisfactory definition of truth should meet.
1.1 Object language and metalanguage
If the language under discussion (the object language) is \(L\), then the definition should be given in another language known as the metalanguage, call it \(M\). The metalanguage should contain a copy of the object language (so that anything one can say in \(L\) can be said in \(M\) too), and \(M\) should also be able to talk about the sentences of \(L\) and their syntax. Finally Tarski allowed \(M\) to contain notions from set theory, and a 1-ary predicate symbol True with the intended reading 'is a true sentence of \(L\)'. The main purpose of the metalanguage was to formalise what was being said about the object language, and so Tarski also required that the metalanguage should carry with it a set of axioms expressing everything that one needs to assume for purposes of defining and justifying the truth definition. The truth definition itself was to be a definition of True in terms of the other expressions of the metalanguage. So the definition was to be in terms of syntax, set theory and the notions expressible in \(L\), but not semantic notions like 'denote' or 'mean' (unless the object language happened to contain these notions).
Tarski assumed, in the manner of his time, that the object language \(L\) and the metalanguage \(M\) would be languages of some kind of higher order logic. Today it is more usual to take some kind of informal set theory as one's metalanguage; this would affect a few details of Tarski's paper but not its main thrust. Also today it is usual to define syntax in set-theoretic terms, so that for example a string of letters becomes a sequence. In fact one must use a set-theoretic syntax if one wants to work with an object language that has uncountably many symbols, as model theorists have done freely for over half a century now.
1.2 Formal correctness
The definition of True should be 'formally correct'. This means that it should be a sentence of the form
For all \(x\), True\((x)\) if and only if \(\phi(x)\),
where True never occurs in \(\phi\); or failing this, that the definition should be provably equivalent to a sentence of this form. The equivalence must be provable using axioms of the metalanguage that don't contain True. Definitions of the kind displayed above are usually called explicit, though Tarski in 1933 called them normal.
1.3 Material adequacy
The definition should be 'materially adequate' (trafny – a better translation would be 'accurate'). This means that the objects satisfying \(\phi\) should be exactly the objects that we would intuitively count as being true sentences of \(L\), and that this fact should be provable from the axioms of the metalanguage. At first sight this is a paradoxical requirement: if we can prove what Tarski asks for, just from the axioms of the metalanguage, then we must already have a materially adequate formalisation of 'true sentence of \(L\)' within the metalanguage, suggesting an infinite regress. In fact Tarski escapes the paradox by using (in general) infinitely many sentences of \(M\) to express truth, namely all the sentences of the form
\[ \phi(s) \text{ if and only if } \psi \]whenever \(s\) is the name of a sentence \(S\) of \(L\) and \(\psi\) is the copy of \(S\) in the metalanguage. So the technical problem is to find a single formula \(\phi\) that allows us to deduce all these sentences from the axioms of \(M\); this formula \(\phi\) will serve to give the explicit definition of True.
Tarski's own name for this criterion of material adequacy was Convention T. More generally his name for his approach to defining truth, using this criterion, was the semantic conception of truth.
As Tarski himself emphasised, Convention \(T\) rapidly leads to the liar paradox if the language \(L\) has enough resources to talk about its own semantics. (See the entry on the revision theory of truth.) Tarski's own conclusion was that a truth definition for a language \(L\) has to be given in a metalanguage which is essentially stronger than \(L\).
There is a consequence for the foundations of mathematics. First-order Zermelo-Fraenkel set theory is widely regarded as the standard of mathematical correctness, in the sense that a proof is correct if and only if it can be formalised as a formal proof in set theory. We would like to be able to give a truth definition for set theory; but by Tarski's result this truth definition can't be given in set theory itself. The usual solution is to give the truth definition informally in English. But there are a number of ways of giving limited formal truth definitions for set theory. For example Azriel Levy showed that for every natural number \(n\) there is a \(\Sigma_n\) formula that is satisfied by all and only the set-theoretic names of true \(\Sigma_n\) sentences of set theory. The definition of \(\Sigma_n\) is too technical to give here, but three points are worth making. First, every sentence of set theory is provably equivalent to a \(\Sigma_n\) sentence for any large enough \(n\). Second, the class of \(\Sigma_n\) formulas is closed under adding existential quantifiers at the beginning, but not under adding universal quantifiers. Third, the class is not closed under negation; this is how Levy escapes Tarski's paradox. (See the entry on set theory.) Essentially the same devices allow Jaakko Hintikka to give an internal truth definition for his independence friendly logic; this logic shares the second and third properties of Levy's classes of formulas.
2. Some kinds of truth definition on the 1933 pattern
In his 1933 paper Tarski went on to show that many fully interpreted formal languages do have a truth definition that satisfies his conditions. He gave four examples in that paper. One was a trivial definition for a finite language; it simply listed the finitely many true sentences. One was a definition by quantifier elimination; see Section 2.2 below. The remaining two, for different classes of language, were examples of what people today think of as the standard Tarski truth definition; they are forerunners of the 1956 model-theoretic definition.
2.1 The standard truth definitions
The two standard truth definitions are at first glance not definitions of truth at all, but definitions of a more complicated relation involving assignments \(a\) of objects to variables:
\[ a \text{ satisfies the formula } F \](where the symbol '\(F\)' is a placeholder for a name of a particular formula of the object language). In fact satisfaction reduces to truth in this sense: \(a\) satisfies the formula \(F\) if and only if taking each free variable in \(F\) as a name of the object assigned to it by \(a\) makes the formula \(F\) into a true sentence. So it follows that our intuitions about when a sentence is true can guide our intuitions about when an assignment satisfies a formula. But none of this can enter into the formal definition of truth, because 'taking a variable as a name of an object' is a semantic notion, and Tarski's truth definition has to be built only on notions from syntax and set theory (together with those in the object language); recall Section 1.1. In fact Tarski's reduction goes in the other direction: if the formula \(F\) has no free variables, then to say that \(F\) is true is to say that every assignment satisfies it.
The reason why Tarski defines satisfaction directly, and then deduces a definition of truth, is that satisfaction obeys recursive conditions in the following sense: if \(F\) is a compound formula, then to know which assignments satisfy \(F\), it's enough to know which assignments satisfy the immediate constituents of \(F\). Here are two typical examples:
- The assignment \(a\) satisfies the formula '\(F\) and \(G\)' if and only if \(a\) satisfies \(F\) and \(a\) satisfies \(G\).
- The assignment \(a\) satisfies the formula 'For all \(x\), \(G\)' if and only if for every individual \(i\), if \(b\) is the assignment that assigns \(i\) to the variable \(x\) and is otherwise exactly like \(a\), then \(b\) satisfies \(G\).
We have to use a different approach for atomic formulas. But for these, at least assuming for simplicity that \(L\) has no function symbols, we can use the metalanguage copies \(\#(R)\) of the predicate symbols \(R\) of the object language. Thus:
- The assignment \(a\) satisfies the formula \(R(x,y)\) if and only if \(\#(R)(a(x),a(y))\).
(Warning: the expression \(\#\) is in the metametalanguage, not in the metalanguage \(M\). We may or may not be able to find a formula of \(M\) that expresses \(\#\) for predicate symbols; it depends on exactly what the language \(L\) is.)
Subject to the mild reservation in the next paragraph, Tarski's definition of satisfaction is compositional, meaning that the class of assignments which satisfy a compound formula \(F\) is determined solely by (1) the syntactic rule used to construct \(F\) from its immediate constituents and (2) the classes of assignments that satisfy these immediate constituents. (This is sometimes phrased loosely as: satisfaction is defined recursively. But this formulation misses the central point, that (1) and (2) don't contain any syntactic information about the immediate constituents.) Compositionality explains why Tarski switched from truth to satisfaction. You can't define whether 'For all \(x, G\)' is true in terms of whether \(G\) is true, because in general \(G\) has a free variable \(x\) and so it isn't either true or false.
The reservation is that Tarski's definition of satisfaction in the 1933 paper doesn't in fact mention the class of assignments that satisfy a formula \(F\). Instead, as we saw, he defines the relation '\(a\) satisfies \(F\)', which determines what that class is. This is probably the main reason why some people (including Tarski himself in conversation, as reported by Barbara Partee) have preferred not to describe the 1933 definition as compositional. But the class format, which is compositional on any reckoning, does appear in an early variant of the truth definition in Tarski's paper of 1931 on definable sets of real numbers. Tarski had a good reason for preferring the format '\(a\) satisfies \(F\)' in his 1933 paper, namely that it allowed him to reduce the set-theoretic requirements of the truth definition. In sections 4 and 5 of the 1933 paper he spelled out these requirements carefully.
The name 'compositional(ity)' first appears in papers of Putnam in 1960 (published 1975) and Katz and Fodor in 1963 on natural language semantics. In talking about compositionality, we have moved to thinking of Tarski's definition as a semantics, i.e. a way of assigning 'meanings' to formulas. (Here we take the meaning of a sentence to be its truth value.) Compositionality means essentially that the meanings assigned to formulas give at least enough information to determine the truth values of sentences containing them. One can ask conversely whether Tarski's semantics provides only as much information as we need about each formula, in order to reach the truth values of sentences. If the answer is yes, we say that the semantics is fully abstract (for truth). One can show fairly easily, for any of the standard languages of logic, that Tarski's definition of satisfaction is in fact fully abstract.
As it stands, Tarski's definition of satisfaction is not an explicit definition, because satisfaction for one formula is defined in terms of satisfaction for other formulas. So to show that it is formally correct, we need a way of converting it to an explicit definition. One way to do this is as follows, using either higher order logic or set theory. Suppose we write \(S\) for a binary relation between assignments and formulas. We say that \(S\) is a satisfaction relation if for every formula \(G, S\) meets the conditions put for satisfaction of \(G\) by Tarski's definition. For example, if \(G\) is '\(G_1\) and \(G_2\)', \(S\) should satisfy the following condition for every assignment \(a\):
\[ S(a,G) \text{ if and only if } S(a,G_1) \text{ and } S(a,G_2). \]We can define 'satisfaction relation' formally, using the recursive clauses and the conditions for atomic formulas in Tarski's recursive definition. Now we prove, by induction on the complexity of formulas, that there is exactly one satisfaction relation \(S\). (There are some technical subtleties, but it can be done.) Finally we define
\(a\) satisfies \(F\) if and only if: there is a satisfaction relation \(S\) such that \(S(a,F)\).
It is then a technical exercise to show that this definition of satisfaction is materially adequate. Actually one must first write out the counterpart of Convention \(T\) for satisfaction of formulas, but I leave this to the reader.
2.2 The truth definition by quantifier elimination
The remaining truth definition in Tarski's 1933 paper – the third as they appear in the paper – is really a bundle of related truth definitions, all for the same object language \(L\) but in different interpretations. The quantifiers of \(L\) are assumed to range over a particular class, call it \(A\); in fact they are second order quantifiers, so that really they range over the collection of subclasses of \(A\). The class \(A\) is not named explicitly in the object language, and thus one can give separate truth definitions for different values of \(A\), as Tarski proceeds to do. So for this section of the paper, Tarski allows one and the same sentence to be given different interpretations; this is the exception to the general claim that his object language sentences are fully interpreted. But Tarski stays on the straight and narrow: he talks about 'truth' only in the special case where \(A\) is the class of all individuals. For other values of \(A\), he speaks not of 'truth' but of 'correctness in the domain \(A\)'.
These truth or correctness definitions don't fall out of a definition of satisfaction. In fact they go by a much less direct route, which Tarski describes as a 'purely accidental' possibility that relies on the 'specific peculiarities' of the particular object language. It may be helpful to give a few more of the technical details than Tarski does, in a more familiar notation than Tarski's, in order to show what is involved. Tarski refers his readers to a paper of Thoralf Skolem in 1919 for the technicalities.
One can think of the language \(L\) as the first-order language with predicate symbols \(\subseteq\) and =. The language is interpreted as talking about the subclasses of the class \(A\). In this language we can define:
- '\(x\) is the empty set' (viz. \(x \subseteq\) every class).
- '\(x\) is an atom' (viz. \(x\) is not empty, but every subclass of \(x\) not equal to \(x\) is empty).
- '\(x\) has exactly \(k\) members' (where \(k\) is a finite number; viz. there are exactly \(k\) distinct atoms \(\subseteq x)\).
- 'There are exactly \(k\) elements in \(A\)' (viz. there is a class with exactly \(k\) members, but there is no class with exactly \(k+1\) members).
Now we aim to prove:
Lemma. Every formula \(F\) of \(L\) is equivalent to (i.e. is satisfied by exactly the same assignments as) some boolean combination of sentences of the form 'There are exactly \(k\) elements in \(A\)' and formulas of the form 'There are exactly \(k\) elements that are in \(v_1\), not in \(v_2\), not in \(v_3\) and in \(v_4\)' (or any other combination of this type, using only variables free in \(F)\).
The proof is by induction on the complexity of formulas. For atomic formulas it is easy. For boolean combinations of formulas it is easy, since a boolean combination of boolean combinations is again a boolean combination. For formulas beginning with \(\forall\), we take the negation. This leaves just one case that involves any work, namely the case of a formula beginning with an existential quantifier. By induction hypothesis we can replace the part after the quantifier by a boolean combination of formulas of the kinds stated. So a typical case might be:
\(\exists z\) (there are exactly two elements that are in \(z\) and \(x\) and not in \(y)\).
This holds if and only if there are at least two elements that are in \(x\) and not in \(y\). We can write this in turn as: The number of elements in \(x\) and not in \(y\) is not 0 and is not 1; which is a boolean combination of allowed formulas. The general proof is very similar but more complicated.
When the lemma has been proved, we look at what it says about a sentence. Since the sentence has no free variables, the lemma tells us that it is equivalent to a boolean combination of statements saying that \(A\) has a given finite number of elements. So if we know how many elements \(A\) has, we can immediately calculate whether the sentence is 'correct in the domain \(A\)'.
One more step and we are home. As we prove the lemma, we should gather up any facts that can be stated in \(L\), are true in every domain, and are needed for proving the lemma. For example we shall almost certainly need the sentence saying that \(\subseteq\) is transitive. Write \(T\) for the set of all these sentences. (In Tarski's presentation \(T\) vanishes, since he is using higher order logic and the required statements about classes become theorems of logic.) Thus we reach, for example:
Theorem. If the domain \(A\) is infinite, then a sentence \(S\) of the language \(L\) is correct in \(A\) if and only if \(S\) is deducible from \(T\) and the sentences saying that the number of elements of \(A\) is not any finite number.
The class of all individuals is infinite (Tarski asserts), so the theorem applies when \(A\) is this class. And in this case Tarski has no inhibitions about saying not just 'correct in \(A\)' but 'true'; so we have our truth definition.
The method we have described revolves almost entirely around removing existential quantifiers from the beginnings of formulas; so it is known as the method of quantifier elimination. It is not as far as you might think from the two standard definitions. In all cases Tarski assigns to each formula, by induction on the complexity of formulas, a description of the class of assignments that satisfy the formula. In the two previous truth definitions this class is described directly; in the quantifier elimination case it is described in terms of a boolean combination of formulas of a simple kind.
At around the same time as he was writing the 1933 paper, Tarski gave a truth definition by quantifier elimination for the first-order language of the field of real numbers. In his 1931 paper it appears only as an interesting way of characterising the set of relations definable by formulas. Later he gave a fuller account, emphasising that his method provided not just a truth definition but an algorithm for determining which sentences about the real numbers are true and which are false.
3. The 1956 definition and its offspring
In 1933 Tarski assumed that the formal languages that he was dealing with had two kinds of symbol (apart from punctuation), namely constants and variables. The constants included logical constants, but also any other terms of fixed meaning. The variables had no independent meaning and were simply part of the apparatus of quantification.
Model theory by contrast works with three levels of symbol. There are the logical constants \((=, \neg\), & for example), the variables (as before), and between these a middle group of symbols which have no fixed meaning but get a meaning through being applied to a particular structure. The symbols of this middle group include the nonlogical constants of the language, such as relation symbols, function symbols and constant individual symbols. They also include the quantifier symbols \(\forall\) and \(\exists\), since we need to refer to the structure to see what set they range over. This type of three-level language corresponds to mathematical usage; for example we write the addition operation of an abelian group as +, and this symbol stands for different functions in different groups.
So one has to work a little to apply the 1933 definition to model-theoretic languages. There are basically two approaches: (1) Take one structure \(A\) at a time, and regard the nonlogical constants as constants, interpreted in \(A\). (2) Regard the nonlogical constants as variables, and use the 1933 definition to describe when a sentence is satisfied by an assignment of the ingredients of a structure \(A\) to these variables. There are problems with both these approaches, as Tarski himself describes in several places. The chief problem with (1) is that in model theory we very frequently want to use the same language in connection with two or more different structures – for example when we are defining elementary embeddings between structures (see the entry on first-order model theory). The problem with (2) is more abstract: it is disruptive and bad practice to talk of formulas with free variables being 'true'. (We saw in Section 2.2 how Tarski avoided talking about truth in connection with sentences that have varying interpretations.) What Tarski did in practice, from the appearance of his textbook in 1936 to the late 1940s, was to use a version of (2) and simply avoid talking about model-theoretic sentences being true in structures; instead he gave an indirect definition of what it is for a structure to be a 'model of' a sentence, and apologised that strictly this was an abuse of language. (Chapter VI of Tarski 1994 still contains relics of this old approach.)
By the late 1940s it had become clear that a direct model-theoretic truth definition was needed. Tarski and colleagues experimented with several ways of casting it. The version we use today is based on that published by Tarski and Robert Vaught in 1956. See the entry on classical logic for an exposition.
The right way to think of the model-theoretic definition is that we have sentences whose truth value varies according to the situation where they are used. So the nonlogical constants are not variables; they are definite descriptions whose reference depends on the context. Likewise the quantifiers have this indexical feature, that the domain over which they range depends on the context of use. In this spirit one can add other kinds of indexing. For example a Kripke structure is an indexed family of structures, with a relation on the index set; these structures and their close relatives are fundamental for the semantics of modal, temporal and intuitionist logic.
Already in the 1950s model theorists were interested in formal languages that include kinds of expression different from anything in Tarski's 1933 paper. Extending the truth definition to infinitary logics was no problem at all. Nor was there any serious problem about most of the generalised quantifiers proposed at the time. For example there is a quantifier \(Qxy\) with the intended meaning:
\(QxyF(x,y)\) if and only if there is an infinite set \(X\) of elements such that for all \(a\) and \(b\) in \(X, F(a,b)\).
This definition itself shows at once how the required clause in the truth definition should go.
In 1961 Leon Henkin pointed out two sorts of model-theoretic language that didn't immediately have a truth definition of Tarski's kind. The first had infinite strings of quantifiers:
\[ \forall v_1 \exists v_2 \forall v_3 \exists v_4\ldots R(v_1,v_2,v_3, v_4,\ldots). \]The second had quantifiers that are not linearly ordered. For ease of writing I use Hintikka's later notation for these:
\[ \forall v_1 \exists v_2 \forall v_3 (\exists v_4 /\forall v_1) R(v_1,v_2,v_3, v_4). \]Here the slash after \(\exists v_4\) means that this quantifier is outside the scope of the earlier quantifier \(\forall v_1\) (and also outside that of the earlier existential quantifier).
Henkin pointed out that in both cases one could give a natural semantics in terms of Skolem functions. For example the second sentence can be paraphrased as
\[ \exists f\exists g \forall v_1 \forall v_3 R(v_1,f(v_1),v_3,g(v_3)), \]which has a straightforward Tarski truth condition in second order logic. Hintikka then observed that one can read the Skolem functions as winning strategies in a game, as in the entry on logic and games. In this way one can build up a compositional semantics, by assigning to each formula a game. A sentence is true if and only if the player Myself (in Hintikka's nomenclature) has a winning strategy for the game assigned to the sentence. This game semantics agrees with Tarski's on conventional first-order sentences. But it is far from fully abstract; probably one should think of it as an operational semantics, describing how a sentence is verified rather than whether it is true.
The problem of giving a Tarski-style semantics for Henkin's two languages turned out to be different in the two cases. With the first, the problem is that the syntax of the language is not well-founded: there is an infinite descending sequence of subformulas as one strips off the quantifiers one by one. Hence there is no hope of giving a definition of satisfaction by recursion on the complexity of formulas. The remedy is to note that the explicit form of Tarski's truth definition in Section 2.1 above didn't require a recursive definition; it needed only that the conditions on the satisfaction relation \(S\) pin it down uniquely. For Henkin's first style of language this is still true, though the reason is no longer the well-foundedness of the syntax.
For Henkin's second style of language, at least in Hintikka's notation (see the entry on independence friendly logic), the syntax is well-founded, but the displacement of the quantifier scopes means that the usual quantifier clauses in the definition of satisfaction no longer work. To get a compositional and fully abstract semantics, one has to ask not what assignments of variables satisfy a formula, but what sets of assignments satisfy the formula 'uniformly', where 'uniformly' means 'independent of assignments to certain variables, as shown by the slashes on quantifiers inside the formula'. (Further details of revisions of Tarski's truth definition along these lines are in the entry on dependence logic.) Henkin's second example is of more than theoretical interest, because clashes between the semantic and the syntactic scope of quantifiers occur very often in natural languages.
- Feferman, S., 2004, "Tarski's conceptual analysis of semantical notions", in Sémantique et Épistémologie, ed. Ali Benmakhlouf, Casablanca: Editions Le Fennec, 79–108; reprinted in Patterson 2008.
- Henkin, L., 1961, "Some remarks on infinitely long formulas", in Infinitistic methods: Proceedings of the symposium on foundations of mathematics, Oxford: Pergamon Press, 167–183.
- Hintikka, J., 1996, The Principles of Mathematics Revisited, Cambridge: Cambridge University Press.
- Hodges, W., 1997, "Compositional semantics for a language of imperfect information", Logic Journal of the IGPL, 5: 539–563.
- –––, 2008, "Tarski's theory of definition", in Patterson 2008, pp. 94–132.
- Katz, J. and Fodor, J., 1963, "The structure of a semantic theory", Language, 39: 170–210.
- Levy, A., 1965, A hierarchy of formulas in set theory, (Memoirs of American Mathematical Society 57), Providence: American Mathematical Society.
- Patterson, D. (ed.), 2008, New Essays on Tarski and Philosophy, Oxford: Oxford University Press.
- Putnam, H., 1975, "Do true assertions correspond to reality?", in Mind, Language and Reality (Philosophical Papers: Volume 2), Cambridge: Cambridge University Press, 70–84.
- Skolem, T., 1919, "Untersuchungen über die Axiome des Klassenkalküls und über Produktations- und Summationsprobleme, welche gewisse Klassen von Aussagen betreffen", Videnskapsselskapets Skrifter, I. Matem.-naturv. klasse, 3; reprinted in T. Skolem, Selected Works in Logic, J. E. Fenstad (ed.), Oslo: Universitetforlaget, pp. 67–101.
- Tarski, A., 1931, "Sur les ensembles définissables de nombres réels. I", Fundamenta Mathematicae, 17: 210–239.
- –––, 1933, "The concept of truth in the languages of the deductive sciences" (Polish), Prace Towarzystwa Naukowego Warszawskiego, Wydzial III Nauk Matematyczno-Fizycznych 34, Warsaw; reprinted in Zygmunt 1995, pp. 13–172; expanded English translation in Tarski 1983 [1956], pp. 152–278.
- –––, 1944, "The semantic conception of truth", Philosophy and Phenomenological Research, 4 (3): 341–376.
- –––, 1983 [1956], Logic, Semantics, Metamathematics: Papers from 1923 to 1938, 2nd edition, John Corcoran (ed.), Indianapolis: Hackett Publishing Company; 1st edition, Oxford: Oxford University Press, 1956.
- –––, 1994 [1936], Introduction to Logic and to the Methodology of the Deductive Sciences, 4th edition, Jan Tarski (ed.), Oxford: Oxford University Press; originally published as O logice matematycznej i metodzie dedukcyjnej (On Mathematical Logic and the Deductive Method), Lwów, Warsaw: Książnica-Atlas, 1936; German translation, Einführung in die mathematische Logik und in die Methodologie der Mathematik, Vienna: Julius Springer-Verlag; first English edition, Oxford: Oxford University Press, 1941; 2nd edition, 1946; 3rd edition, 1985.
- Tarski, A. and Vaught, R., 1956, "Arithmetical extensions of relational systems", Compositio Mathematica, 13: 81–102.
- Woleński, J., 2019, Semantics and Truth, Cham: Springer.
- Zygmunt, J. (ed.), 1995, Alfred Tarski, Pisma Logiczno-Filozoficzne, 1 Prawda, Warsaw: Wydawnictwo Naukowe PWN.
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Grapefruit Bitters
I go through drink trends. I've been in the Very Dirty Gin Martini phase, the Flavored Vodka or Gin and Tonic phase, the Old Fashioned phase, and the Gimlet phase, but right now I'm in a Manhattan phase. After sitting on the river this summer and watching the sun set behind the Manhattan skyline while sipping the drink by the same name, I've been ordering these occasionally to remember the slow beauty of that warm evening. Because of this, I've been exploring what makes a Manhattan a Manhattan, and playing with the simple ingredients. Essential to keeping the drink complex and interesting is the slight drip of bitters.
Once upon a time, bitters served as a health tonic, and every medical quack had his own version or two. Now, there are only a few brands available to the home bartender. After an afternoon of research, I learned that bitters were accomplish-able at home, and with the mountains of grapefruit available around here this time of year, I decided to start with grapefruit bitters. This recipe is very slightly adapted from an exploration of bitters in an LA Times article a few years back. This is very, very bitter, very clean, and incredibly aromatic. The coriander emphasizes the fragrance of the grapefruit, adding a complex winey-ness. A little of this goes a long way, which is exactly how it should be.
You will need:
2 cups clean tasting, high proof vodka
2 large grapefruit, scrubbed clean
1 tablespoon coriander seed
4 tablespoons sugar
2 tablespoons water
To make the bitters:
Peel the grapefruit, and dice the peel, white pith and all, into small chunks. Toss the diced peel in a quart mason jar, then add the vodka and coriander. (Juice the remaining fruit or use it in another application.) Place the jar in a cool, dark place for one week.
After one week, strain the liquid into a clean mason jar then discard the diced peel and coriander. In a small saucepan, heat the sugar until it is medium brown. Remove from heat, carefully add the water, and stir until the water dissolves the sugar. Let the mixture come to room temperature.
Once cooled, pour the sugar mixture into the mason jar. Lid the jar and set it aside for an hour or so as the flavors meld and settle. Carefully funnel the bitters into a bottle and label.
This makes approximately two cups.
I'll sip this in a homemade Manhattan; no, the skyline won't be shooting up in front of me this time. Instead, I'll be in my flipflops in the backyard, the lemon and orange blossoms will be blooming, the wild parrots will be squawking, and I'll be perfectly content.


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Human activities are advancing the spread of vector-borne, zoonotic diseases such as West Nile virus, Lyme disease and dengue fever, report scientists publishing a series of papers today in the journal The Lancet.
Vector-borne zoonotic diseases result from disease-causing agents or pathogens that naturally infect wildlife, and are transmitted to humans by carriers such as mosquitoes and ticks. In short, they're diseases transmitted between animals and humans.
Widespread land-use change, globalization of trade and travel, and social upheaval are driving the emergence of zoonotic diseases around the world, said biologist Marm Kilpatrick, who studies the ecology of infectious diseases at the University of California, Santa Cruz.
Kilpatrick co-authored one of several papers in The Lancet, along with Sarah Randolph of the University of Oxford. The Lancet papers are part of a special series in the journal focused on emerging zoonotic diseases.
"Increasing human population, and the urbanization and agricultural intensification of landscapes, put strong selective pressure on vector-borne pathogens to infect humans—and to be transmitted by vectors and hosts that live around humans," Kilpatrick said.
"Humans are altering the environment and moving ourselves and other organisms around the globe at an ever-increasing pace," said Sam Scheiner, a program director for the Ecology and Evolution of Infectious Diseases (EEID) program at the National Science Foundation. "Our fast-track has led to a growing disease threat."
EEID is a joint effort with NSF and the National Institutes of Health. At NSF, the Directorate for Biological Sciences and Directorate for Geosciences fund the program.
EEID funded much of the research discussed in The Lancet papers. "These papers show how and why zoonotic diseases are emerging, and what we need to know to ease the disease burden," said Scheiner.
The papers "offer a bridge between ecologists and clinicians whose combined efforts are needed to address the ongoing challenges of emerging zoonotic diseases," said Kilpatrick, who coauthored research with Sarah Randolph of the University of Oxford.
Added scientist Peter Daszak, president of the EcoHealth Alliance in New York City and author of a paper in the series, "Pandemic zoonoses such as SARS, Ebola and HIV/AIDS are devastating when they emerge. What this series shows is that we have new ways of predicting their origins, of discovering them even before they reach our population—truly a brave new world for pandemic prevention."
There are roughly two types of emerging infectious diseases: introduced and locally emerging.
Introduced diseases arise from the spread of a pathogen to a new location, as when West Nile virus arrived in New York in 1999 and subsequently spread across North America.
Locally emerging diseases increase in importance in areas where they are endemic, as with Lyme disease in the United States during the past three decades.
These two types of emerging diseases can differ markedly with respect to infection dynamics or the number of cases over time, Kilpatrick said.
"Introduced diseases often cause a big spike in infections, and then decrease substantially. Locally emerging diseases often show a steady, sustained rise."
The movement of pathogens by global trade and travel results in the emergence of diseases in new regions.
Once established, introduced pathogens often evolve to take advantage of their new environments, including new hosts and vectors.
With much of the landscape shaped by human activities, pathogens may thrive by infecting hosts and vectors that do well in man-made environments.
Emergence of endemic vector-borne diseases can result from changes in land use, such as movement of people into new habitats, or environmental changes that affect wild animals that serve as natural hosts—and the insect vectors that spread the disease to humans.
Although vector-borne diseases are sensitive to climate, climate change does not appear to be a major driving force behind emerging diseases.
"So far, climate change has been a relatively minor player compared to land use and socioeconomic factors in the emergence of vector-borne disease," Kilpatrick said.
Social and economic changes, ranging from economic downturns to displacement of populations by armed conflict, frequently precipitate disease outbreaks through their effects on public health systems, sanitation systems, behavioral patterns and uses of natural environmental resources.
The incidence of any vector-borne disease involves a complex interplay of multiple factors affecting animal hosts, vectors and people.
Kilpatrick and Randolph emphasize that control of these diseases requires combined efforts by clinicians and public health officials to treat patients; promote behavior likely to minimize the risk of infection; and advise on efforts to reverse the ecological drivers of transmission through vector control, urban planning and ecological restoration.
The Lancet papers are published ahead of a special 20th anniversary symposium to be held on Dec. 11 and 12, 2012, in Washington, D.C.
The symposium is hosted by the National Academies' Institute of Medicine's Forum on Microbial Threats. The symposium will take a retrospective look at the Institute of Medicine's 1992 reports on Emerging Infections and its 2003 Microbial Threats to Health, as well as its creation of the forum in 1996.
Zoonoses disease series at The Lancet
Source: National Science Foundation


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The average monthly rent of apartments in Lake Wales, FL is $1,424.
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6 Rentals Available
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CES Innovations Award double-winner offers look into innovative tech products for streaming entertainment, cloud-based video monitoring and high performance connectivity
LAS VEGAS — January 7, 2013 — NETGEAR®, Inc. (NASDAQGM: NTGR) (www.netgear.com), a global networking company that delivers innovative products to consumers, businesses and service providers, today unveiled a roster of powerful new connectivity solutions for the "smart" home at a press conference held in conjunction with the opening of the International Consumer Electronics Show (CES®) in Las Vegas. NETGEAR launched a number of new WiFi, networking and media streaming products that demonstrate the company's leadership in technologies that are transforming the connected home and entertainment experience. You can read today's other CES-related announcements from NETGEAR at netgear.com/about/press-releases/.
NETGEAR is focused on leading the revolution in how people around the world use connected devices that take advantage of "cloud computing" whether they're at home, at work or on the go. The industry clearly recognizes this aim, as NETGEAR is a double-honoree this year in the CES Innovations Design and Engineering Awards competition, the industry's highest accolade, for VueZone® Add-On Night Vision Camera (VZCN2060) and NeoTV® MAX Streaming Player (NTV300SL).
"NETGEAR has always been dedicated to helping you simply do more with your home network, and thanks to new mobile devices that work in the cloud, your connectivity options have expanded from fundamental to fantastic," said Patrick Lo, CEO of NETGEAR. "This year at CES, we shine a spotlight on how we're ensuring seamless connectivity and control of your home network. This includes more products that take advantage of the cloud to incorporate mobile controls and apps so that you can monitor, set, manage and do more, wherever you are — and with the performance, ease-of-use and reliability that you've come to expect from NETGEAR. We help you to connect TVs to the Internet, supercharge and extend the reaches of your network, and monitor what's going on at home via the cloud, whether you're at home or away. We want to help you make your house the smartest home in the neighborhood."
Monitoring Your Home and Streaming Your Favorite Entertainment Content
NETGEAR has expanded the NETGEAR VueZone Home Monitoring product line with the NETGEAR VueZone Add-On Night Vision Camera (VZCN2060), a CES Innovations Award honoree. It's a two-part system: a powerful AC-powered infrared lamp along with the only wire-free night vision camera that lets you see in the dark. The camera is suitable for both daytime and nighttime use and can be set to automatically detect motion, record an event and send an alert. You can play back your recorded videos from anywhere on Apple iOS or Google Android™ smartphones and tablets, or on PCs or Mac computers. Use your smartphone to easily keep an eye on children, elderly relatives, pets, property, vacation homes or businesses, from anywhere at any time. For more information, please visit www.netgear.com/nightvision.
Building on the features of the NETGEAR NeoTV, NeoTV PRO and NeoTV MAX family of streaming players, the new NETGEAR NeoTV PRIME with Google TV (GTV100) streaming player extends your entertainment experience beyond just streaming video or even basic TV viewing. It enables you to easily find what you love to watch —whether it's on live TV, streaming entertainment, apps, or the web— using one small NeoTV player. NeoTV PRIME opens up the world of apps from Google Play, delivering access to a growing library of entertainment including movies, TV shows, and music from streaming services such as Netflix, Amazon Instant Video, HBO Go, Crackle, Flixter, Rhapsody, Pandora and many more. Visit www.netgear.com/gtv100 to learn more about NeoTV PRIME with Google TV.
NETGEAR has also added Sling Media's SlingPlayer® to a growing list of hundreds of existing streaming channels on the NETGEAR line of NeoTV Streaming Players — NeoTV (NTV300), NeoTV PRO (NTV300S), the 2013 CES Innovations Award honoree NeoTV MAX (NTV300SL), or the just-announced NeoTV PRIME with Google TV™ (GTV100). With the combination of a NETGEAR NeoTV Streaming Player and a Slingbox®, you can now easily enjoy streaming of your favorite live TV shows, sporting events, recorded programming and even premium movies on any TV using your Internet connection. Find more information on NeoTV Streaming Players at www.netgear.com/landing/stream/tv/#neotv.
Accessing Entertainment on Your Home Network and Mobile Devices Through the Cloud
At CES, NETGEAR is debuting the NETGEAR Universal Dual Band WiFi Range Extender, Wall-plug Edition (WN3500RP). It amplifies both WiFi network frequency bands, giving you a greatly improved wireless experience throughout your home for WiFi connected devices including tablets, laptops, smart TVs, smartphones and more. It's the first WiFi range extender that can also be directly connected to speakers for music streaming using AirPlay® from devices such as the iPhone® and iPad®, or DLNA® for wireless audio streaming from Android™ smartphones, while at the same time amplifying an existing network connection. To learn more about the NETGEAR Universal Dual Band WiFi Range Extender and the family of easy-to-use WiFi range extenders, please visit: www.netgear.com/home/products/networking/wifi-range-extenders/WN3500RP.aspx.
To make it even easier to manage your home network, NETGEAR is demonstrating at CES several upcoming enhancements to its popular NETGEAR genie®, a simple, elegant application for your computer or mobile device to easily manage, monitor and repair your NETGEAR home network. You can download the free genie app at www.netgear.com/genie or from the Google Play or App Store. NETGEAR customers have now downloaded and installed NETGEAR genie over one million times worldwide! Here is what you can look forward to in early 2013:
- NETGEAR genie EZ Mobile Connect is an incredibly easy way to enable your guests' smartphones or tablets to connect to your home Wi-Fi network, simply by scanning the QR code from the genie WiFi screen without typing in security keys or SSIDs. It provides quick and easy wireless connectivity to either the full home network or guest WiFi network.
- With the TurboTransfer feature, you can easily and quickly share files and folders among various desktop and mobile devices in your home network by simply dragging and dropping, or selecting a device from the network map.
- The in-depth WiFi analytics within genie for Android devices help you measure the signal strength of your wireless network across your home, avoid interference from neighboring networks, and more.
- The MyMedia™ mobile app is enhanced for browsing and photo swiping, making it easy for you to find, remotely control, and stream photos and other digital media throughout your home.
- User-based Parental Controls enable you to set different Internet access rules for each computer, smartphone, or tablet on your network.
- A new Powerline Network MAP on genie Desktop for Windows PCs enables you to see the Powerline devices on your network, measure the speed between them, and customize the device settings.
Supporting High Performance Connectivity in Your Smart Home
In 2012, NETGEAR was the first to announce wireless routers to take advantage of the next evolution in wireless technology, 802.11ac. In 2013, NETGEAR is enhancing the capabilities of those products by adding Beamforming technology, which the company is highlighting at CES. NETGEAR Beamforming technology recognizes the location of a wireless device on your network and directs the WiFi signal directly at the device, constantly checking and tracking moving devices such as your mobile phones and tablets. This targeted approach helps each device gain optimal WiFi signal strength, resulting in better performance and a more reliable connection. NETGEAR 802.11ac products that will include Beamforming include the NETGEAR R6300 WiFi Router, the industry's first 802.11ac router offering Gigabit speeds; the NETGEAR R6200 WiFi Router; and the NETGEAR A6200 WiFi USB Adapter with 802.11ac Dual Band. More information on next-generation 802.11ac WiFi technology, including Beamforming, is at www.netgear.com/landing/80211ac/.
NETGEAR is also expanding the 802.11ac family with the introduction of NETGEAR D6200 WiFi DSL Modem Router, the first router available in the United States that incorporates 11ac with ADSL2+ and eliminates the need for a separate DSL modem. The D6200 WiFi Modem Router enables fifth-generation WiFi (5G WiFi), with speeds approximately 300 Mbps (@ 2.4 Ghz 802.11n) + 867 Mbps (@ 5 Ghz 802.11ac) for improved speed and range. It offers backward compatibility to 802.11a, b, g and n, making it perfect for supporting current and future WiFi devices. Ideal for HD gaming and video streaming throughout your home, the NETGEAR D6200 WiFi DSL Modem Router also includes a separate gigabit Ethernet WAN port, making it ready for connecting to fiber optic broadband or high-speed cable modems. You can switch between cable, fiber optic broadband or ADSL without having to reconfigure your home network or replace your router. Visit http://www.netgear.com/home/products/networking/dsl-modems-routers/d6200.aspx for more information on the D6200 WiFi Modem Router.
At CES, NETGEAR will showcase the first Hybrid Networking product based on the IEEE 1905 interoperability standard, which combines the flexibility of wireless (WiFi 802.11n) with the performance of wires (Powerline) to enable the next-generation networked home. By incorporating Hybrid Networking technology with advanced features such as fail over, load balancing, self-organizing networks and aggregation, NETGEAR offers a unique solution for improved coverage, speed and quality of service, which are critical points for the delivery of multiple streams of video or sustainable multiple Internet connections at home.
In addition, NETGEAR will demonstrate two recently announced Powerline products at CES. The NETGEAR Music Extender kit (XAUB2511) is a unique solution using Airplay® technology for playing your music, wirelessly, from your computer or smart phone or tablet, in any room, on any stereo system. The NETGEAR Powerline 500 WiFi Access Point Kit (XWNB5201) turns any power outlet at home into a high-speed WiFi access point using 500Mbps Powerline technology, making it ideal for extending your WiFi coverage across the walls and floors and connecting devices like tablets, laptops and smartphones to fast wireless Internet. Visit netgear.com/home/products/networking/powerline/ for more information on NETGEAR Powerline products for work and play.
Service Providers Choose NETGEAR
NETGEAR high-performance products are also the networking solutions of choice for some of the country's leading broadband service providers and systems installers due to their ease of installation and support. At CES, NETGEAR unveiled NeoMedia™, a new integrated technology platform for media gateways powered by Maelstrom® software from Digital Keystone, (www.digitalkeystone.com), the leader in media distribution software. NeoMedia is the industry's first platform that delivers broadcast and personal content to multiple screens without the need for middleware on the Customer Premise Equipment (CPE).
Connect with NETGEAR Executives at CES Conferences
NETGEAR executives will speak at two key CES conferences, offering their expert perspectives on the future of connectivity and storage in home and business environments.
At the Developer University at CES, Cedar Milazzo will discuss the NETGEAR Smart Network platform, which gives developers the power to produce embedded and cloud applications for consumer and small-business network devices such as gateways, routers, and network attached storage. Cedar will give his presentation in Room S228 of the Las Vegas Convention Center at 3:30 p.m. on January 10.
In the Storage Visions event at CES, Matt Pahnke will explore the home and business storage space, looking at new ways families and teams should organize, back up, share and manage their rich personal and commercial content. Matt's panel discussion is in Room E2 of the Riviera Conference Center at 4:30 p.m. on January 7.
More Information
Read the other CES-related announcements from NETGEAR at netgear.com/about/press-releases/. To learn about other NETGEAR products and services for consumers, businesses and service providers, please visit www.netgear.com.
About NETGEAR, Inc.
NETGEAR (NASDAQGM: NTGR) is a global networking company that delivers innovative products to consumers, businesses and service providers. For consumers, the company makes high performance, dependable and easy to use home networking, storage and digital media products to connect people with the Internet and their content and devices. For businesses, NETGEAR provides networking, storage and security solutions without the cost and complexity of big IT. The company also supplies top service providers with retail proven, whole home solutions for their customers. NETGEAR products are built on a variety of proven technologies such as wireless, Ethernet and Powerline, with a focus on reliability and ease-of-use. NETGEAR products are sold in approximately 25,000 retail locations around the globe, and through approximately 40,000 value-added resellers. The company's headquarters are in San Jose, Calif., with additional offices in over 25 countries. More information is available at www.NETGEAR.com or by calling (408) 907-8000. Connect with NETGEAR at twitter.com/NETGEAR and www.facebook.com/NETGEAR.
©2013 NETGEAR, Inc. NETGEAR, the NETGEAR logo, genie, MyMedia, NeoMedia, NeoTV and VueZone are trademarks and/or registered trademarks of NETGEAR, Inc. and/or its subsidiaries in the United States and/or other countries. Other brand names mentioned herein are for identification purposes only and may be trademarks of their respective holder(s). Information is subject to change without notice. All rights reserved.
* Maximum wireless signal rate derived from IEEE standard 802.11 specifications. Actual data throughput and wireless coverage will vary. Network conditions and environmental factors, including volume of network traffic, building materials and construction, and network overhead, lower actual data throughput rate and wireless coverage. NETGEAR makes no express or implied representations or warranties about this product's compatibility with any future standards.
Safe Harbor Statement under the Private Securities Litigation Reform Act of 1995 for NETGEAR, Inc.: This press release contains forward-looking statements within the meaning of the U.S. Private Securities Litigation Reform Act of 1995. Specifically, statements concerning NETGEAR's business and the expected performance characteristics, specifications, reliability, market acceptance, market growth, specific uses, user feedback and market position of NETGEAR's products and technology are forward-looking statements within the meaning of the Safe Harbor. These statements are based on management's current expectations and are subject to certain risks and uncertainties, including, without limitation, the following: the actual price, performance and ease of use of NETGEAR's products may not meet the price, performance and ease of use requirements of customers; product performance may be adversely affected by real world operating conditions; failure of products may under certain circumstances cause permanent loss of end user data; new viruses or Internet threats may develop that challenge the effectiveness of security features in NETGEAR's products; the ability of NETGEAR to market and sell its products and technology; the impact and pricing of competing products; and the introduction of alternative technological solutions. Further information on potential risk factors that could affect NETGEAR and its business are detailed in the Company's periodic filings with the Securities and Exchange Commission, including, but not limited to, those risks and uncertainties listed in the section entitled "Part II - Item 1A. Risk Factors," pages 46 through 65, in the Company's quarterly report on Form 10-Q for the fiscal quarter ended September 30, 2012, filed with the Securities and Exchange Commission on November 6, 2012. NETGEAR undertakes no obligation to release publicly any revisions to any forward-looking statements contained herein to reflect events or circumstances after the date hereof or to reflect the occurrence of unanticipated events.
U.S. Media Contact:
Claudia Oropeza, Weber Shandwick for NETGEAR, (408) 685-0618, email@example.com
U.S. Sales Inquiries: (408) 907-8000, email@example.com
U.S. Customer Inquiries: (888) NETGEAR


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Saturday 18 September 2010
Sat 18th Sept: Yang du - New Gen exhibition
I finally met Yang Du who I gave her very first press to! (Check it out, I mention MVDH before he's even graduated!)
I want EVERYTHING from her new collection, including the woolly anima hats knitted to look like exact replicas of Mexican finger puppets.
Sat 18th Sept: CASSETTE PLAYA INTERACTIVE DIGITAL INSTALLATION
Rowdy and I having fun trying out Carri's digital photo booth
Friday 17 September 2010
Friday 17th Sept: Hannah Marshall bringing sexy back
Hannah Marshall is bringing sexy back - literally - with a sheer panel cut through the back of a blazer. The front was equally revealed with transparent shirts and figure hugging mesh dresses as if answering "LOVE" magazine's ode to the beauty of boobs. Staggered stiff suede fins jutted out from ivory, beige, grey and mint seperates and fluid organza frills billowed behind structured straps. Its distinctively empowering Marshall encasing tailoring but bending slightly to a softer feminine side. The secret was unlocked in an opening sequence by Rankin film with breasts laid bare, all but for a swathe of silk blowing across the muse's body.
(top to bottom: Miss Marshall, detail of blouse, runway, film, team Marshall in Marshall, supporters Judy Blame and NOKI rocking a Fear&Loathing look, front row honeys Paloma Faith Gemma Cairney Shingai Shinowa)
Friday 17th Sept: KM3D-1 for AnOther
Here it is - fashion's first 3D film. Dammit Elisha wanted to do it but the £45, 000 figure budget required for a 1min short posed us a slight obstacle! So when I found out that AnOther Magazgine had commissioned Baillie Walsh to capture Kate Moss in 3D (leading on from their ground breaking holographic Alexander McQueen A/W 2006 show) I was desperate to check it out! Last night was the official preview of the experience at The Haunch of Venison on a triptych of screens. I grabbed the necessary specs and dashed in like a contestant on the Crystal Maze, frenzied with anticipation of the unknown. What unveiled before me were crystals and diamonds floating in inertia, flung from out of the screen by a screaming possessed goddess Kate Moss. It is incredible. The gems appear to be literally floating around, as if you could touch the facets of the very surface if you reached into the middle distance. All of a sudden a white-noise sound breaks and a giant spinning gem shatters and explodes in a sonic boom. Moss's wild and flowing hair is mimicked in a shower of splintered crystal rain. Its bloody brilliant. I was transported to the childish wonder and fun of the scene where Charlie is floating around the bubble room in the Chocolate Factory.
Now for the technical bit - it was captured at 1,000 frames per second with state -of-the-art Phantom cameras, specially built for the project to create slow motion formations in 3D. To enjoy the experience for yourself buy an issue of AnOther to get the red & blue lens glasses and log onto AnOther from 14:00 hrs today.
Congrats to Ballie for this hypnotic revelation.......
..... lets look back at some of his others..........Massive Attack - Unfinished Symphony (styled by Leigh Bowery) ............ Kylie Minogue - Slow.............. and Will Young - Leave Right Now, and his feature film "Flashbacks of a Fool" with costumes by Stevie Stewart.
Boy George - Generations Of Love (which features Leigh Bowery and Les Child).
Thursday 16 September 2010
Thurs 16th Sept: Bestival with The Cocknbullkid & ROWDY SUPERST*R
Thanks to ROWDY SUPERST*R for sending images from Bestival to conclude my coverage of this year's summer of festivals. Here he is with our fave girrrrrl The Cocknbullkid who performed and gave an interview for T4 which will air this Sunday. Look out for presenter Gemma Cairney who borrowed some of my accessories to wear when presenting the show and read her report at Company mag.
ROWDY is going to be performing at Matthew Herbert's album launch next week, watch the trailer here ft. props on stage by Rosy Nicholas.
Tuesday 14 September 2010
Thurs 16th Sept: "Cherry On The Cake" - Paper @ The V&A
I don't know about you, but one of my favourite parts about a museum visit is ending up in the gift shop! The Science Museum's collection of gizmos, gadgets and 3D specs is worth a visit without seeing the rest of the galleries! Meanwhile, over the road, the V&A gift shop is like a luxury accessories boutique, with the best books any birthday money can buy! So when the team approached me to design something for the 3rd edition of the 'Cherry on the Cake' designer collection, I was over the moon! I'm really enjoying having opportunities to tick off life-long dreams, and this is one of them! I'm ecstatic to think that excitable young creatives can pick up an accessories kit in the gift shop - as I would have been when I was younger.
The"Paper" collection focuses on the medium bringing together 12 artists working in traditional printmaking, paper engineering, typography and paper-cut techniques. My personal favourites are Charlotte Mann, Tom Martin, Rob Ryan and Chisato Tamabayashi.
Check out the whole range on display in the V&A Shop and online at www.vandashop.com
My piece is entitled "Cut Out & Keepsakes" - its a cardboard kit to make your own accessories which I designed based on a research trip to The Museum of Childhood. That was a chore - NOT! Here is the kit made up and displayed in a case of the gift shop and a photo of a detail of the type of paper cuts I make for gift cards which I also wanted to echo. (This is the 2nd product that I have had produced without the sticker sheet I'm still desperate to get made................ any sticker companies listening out there............please give me a ring!)
Watch the La Roux - Bulletproof video featuring my dodecahedron shapes that Ive reinterpreted for the range - here.
Weds 15th Sept: Good One x Topshop - Report by Emily Beard
(Photos of Nin working on the new S/S collection at the Good One studio)
Goodone, a label famous for making knitwear items using reclaimed fabrics and 'Upcycling', has sold its collection for the Autumn/Winter 2010 season to high street giant Topshop.
Following a BFC sponsorship (where they were handpicked by Yasmin Sewell), and 3 fashion week exhibitions with Esthetica, the collection was bought outright by Topshop. The line will debut next week to coincide with London Fashion Week. The clothes (retailing between £70-£225) include body-hugging dresses with quilted hips and shaping side panels, a bomber in chunky Aran knit, and cropped hoodies. In addition to being sold online, the collection will be sold through Topshop's flagship Oxford Circus shop (see Top Shop blog). Separately from Topshop, the collection will also be sold on yoox.com.
The brand also announced it has joined forces with supermarket chain Tesco. This will culminate in an online diffusion line being sold by the retailer in October. This collection includes panelled and wrap dresses, leggings and skirts. In true Good One style, the line will be constructed entirely from ends of rolls and factory waste from a green factory in Sri Lanka.
(Crochet Body available at Top Shop from next week............)
(Preview of 2 looks from new S/S 2011 collection which will be exhibited as part of Esthetica)
Tues 14th Sept: "Smoke And Mirrors" by James Copeman
According to Wikepedia and general knowledge, Paloma Faith was once a Magician's Assistant. The previous incarnation which has conveniently contributed to her unique charismatic stage performance is now written into the narrative of her new video. Director James Copeman's kitsch, sharp witted idiosyncratic style has captured Faith's intrinsic British sassy & saucy sensibility for Smoke & Mirrors.
"she wanted to show a miserable and repetitive life of a magicians assistant. I thought of setting it in a very English b&b and that she should murder him at the end :)
He is actually the magician that she used to work with"
Here are some of James trademark Polaroids from the shoot of Paloma in the incredible outfits which she donnes as the Magician's assistant. I love the way the giant sequin plumed headdress knocks the grannies round the head in the b&b as she serves them tea. I also love that this aesthetic is totally true to her Burlesque roots and that she has always held on to her own look without surrendering to record company criteria. I will never forget the first time I saw Paloma perform in an Easter Island tropical theme club in South London wearing a cute little Sailor's outfit.
To see more of Jame's Polaroids and read the 3 part interview I did with him in 2009, click here.
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Railroad engineers accepted their deal with the railroads that will deliver 24% raises but conductors rejected theirs, threatening the health of the economy just before the holidays and casting more doubt on whether the industry will be able to resolve the labor dispute before next month's deadline without the help of Congress.
Even the threat of a work stoppage could tangle the nation's supply chain as railroads will freeze shipments of chemicals and other goods that could create hazards if disrupted midway to their destination.
A split vote Monday from the two biggest railroad unions follows the rejection by three other unions of their deals with the railroads that the Biden administration helped broker before the original strike deadline in September. Seven smaller unions have approved the five-year deal that, on top of the 24% raise, includes $5,000 in bonuses.
But many union members have voted to reject the contracts because, they say, they fail to address demanding schedules and quality of life issues for employees.
All 12 must approve the contracts to prevent a strike that could cripple supply chains and hamper a stressed U.S. economy still emerging from the pandemic.
The Retail Industry Leaders Association said a rail strike "would cause enormous disruption to the flow of goods nationwide" although retail stores are well stocked for the crucial holiday shopping season.
"Fortunately, this year's holiday gifts have already landed on store shelves. But an interruption to rail transportation does pose a significant challenge to getting items like perishable food products and e-commerce shipments delivered on time, and it will undoubtedly add to the inflationary pressures already hitting the U.S. economy," said Jess Dankert with the group that represents more than 200 major retailers.
The unions that rejected their deals agreed to return to the bargaining table to try to hash out a new agreement before a new strike deadline early next month. But those talks have deadlocked because the railroads refuse to consider adding paid sick time to what was already offered.
It appears increasingly likely that Congress will have to step in to settle the dispute. Lawmakers have the power to impose contract terms if both sides can't reach an agreement. Hundreds of business groups have urged Congress and President Joe Biden to be ready to intervene if needed.
Workers frustrated with the demanding schedules and deep job cuts in the industry pushed to reject these contracts because they don't resolve workers' key quality-of-life concerns. The deals for the engineers and conductors did include a promise to try to improve the scheduling of regular days off and negotiate the details of those schedules further at each railroad. The unions that represent engineers and conductors also received three unpaid days off a year to tend to medical needs as long they were scheduled at least 30 days in advance.
The railroads also lost out on their bid to cut crew sizes down to one person as part of the negotiations. But the conductors in the Transportation Division of the International Association of Sheet Metal, Air, Rail and Transportation Workers union still narrowly rejected the deal with roughly 51% voting against it. A smaller division of the SMART-TD union that represents about 1,300 yardmasters did approve the deal.
"The ball is now in the railroads' court. Let's see what they do. They can settle this at the bargaining table," SMART-TD President Jeremy Ferguson said. "But, the railroad executives who constantly complain about government interference and regularly bad-mouth regulators and Congress now want Congress to do the bargaining for them."
The railroads maintain that the deals with the unions should closely follow the recommendations made this summer by a special panel of arbitrators Biden appointed. That's part of the reason why they don't want to offer paid sick time. Plus, the railroads say the unions have agreed over the years to forgo paid sick time in favor of higher pay and strong short-term disability benefits.
The unions say it is long overdue for the railroads to offer paid sick time to workers, and the pandemic highlighted the need for it.
The group that negotiates on behalf of the railroads said Monday that the unions that rejected their deals shouldn't expect to receive more than the Presidential Emergency Board of arbitrators recommended. The National Carriers Conference Committee said businesses could start to be affected by the threat of a strike even before the deadline because railroads will start curtailing shipments of dangerous chemicals and perishable cargo days ahead of the deadline.
"A national rail strike would severely impact the economy and the public. Now, the continued, near-term threat of one will require that freight railroads and passenger carriers soon begin to take responsible steps to safely secure the network in advance of any deadline," the railroads said.
It's unclear what Congress might do given the deep political divisions in Washington D.C. and a single lawmaker could hold up a resolution. But the head of the Association of American Railroads trade group, Ian Jefferies, said "if the remaining unions do not accept an agreement, Congress should be prepared to act and avoid a disastrous $2 billion a day hit to our economy."


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East New York Farms is building food security and providing jobs for its neighborhood.
December 1, 2010
In a rare demonstration of bipartisanship, the Senate passed the most sweeping food safety reform bill in seven decades Tuesday morning. Despite high tempers in the wake of a contentious cycle, the upper chamber voted 73-25 vote to approve S. 510, the FDA Food Safety Modernization Act, a bill that would increase the Food and Drug Administration's fractured oversight of an increasingly globalized food supply.
Though the bill's passage–lauded by the major food industry, consumer, and public health groups–follows a similar measure that passed the House with bipartisan support in July 2009, the road ahead for comprehensive food safety reform is uncertain. With the clock running on the lame duck session, most advocates for the bill want to see the House take up the Senate version as soon as possible to get the legislation to President Obama's desk.
In a statement yesterday, Obama called on the House to act quickly on the legislation. "I urge the House–which has previously passed legislation demonstrating its strong commitment to making our food supply safer–to act quickly on this critical bill, and I applaud the work that was done to ensure its broad bipartisan passage in the Senate."
Sen. Tom Harkin (D-IA), a key proponent of the measure in the Senate, indicated before Thanksgiving that key leaders in the House agreed to take up the Senate version, but it is not clear that is the game plan for House leadership. The House version of the bill requires far more frequent inspections, augments the cost of the bill with a flat $500 fee for each food facility, and does not contain a hard-fought amendment to exempt small farms and food producers from certain new regulations.
House lawmakers who worked tirelessly to get bipartisan support for their version in 2009 have been noncommittal about adopting the Senate version.
"The Senate bill makes improvements to FDA's existing authorities to ensure the safety of the American food supply just as the House bill does," Rep. John Dingell (D-MI), who has been working on food safety legislation for years, said yesterday. "I commend my colleagues for their hard work over the past year and four months. However, there are some remaining concerns with the final Senate legislation, but the Senate bill is a still a giant leap forward toward ensuring the safety of the American food supply."
"I look forward to discussing the Senate bill with my House colleagues and determining what the appropriate next steps should be to ensure that we provide the greatest protections for American's consumers," added Dingell.
To add to the uncertainty in the House, large produce industry groups, including the United Fresh Produce Association and the Produce Marking Association, are working feverishly to convince lawmakers that the final legislation should not include the small farm exemptions, which were recently adopted into the Senate bill at the urging of Sens. Jon Tester (D-MT and Kay Hagan (D-NC).
The Tester-Hagan amendment intends to protect small farmers and the burgeoning local food movement from cumbersome regulation. The larger produce industry, which is in favor of broad safety requirements to help prevent dangerous and economically damaging foodborne illness outbreaks, has remained squarely against any blanket exemptions based solely on farm size or geography.
"We're pushing for a conference and for the removal of the Tester amendment. We think there is time to do conference," Robert Guenther, executive vice president of public policy at United Fresh, said yesterday. "[The amendment] fundamentally undermines the entire legislation, the rest of the bill is science- and risk-based."
Guenther said the industry would continue to push against the amendment, which he called "arbitrary" and "politically expedient."
Though disagreements remain, the prospect of a conference committee to iron out key differences is seriously in question with so many competing items on the Congressional agenda–including the Bush-era tax cuts and the defense reauthorization bill, which includes a provision to repeal the controversial "don't ask, don't tell" policy.
Casting further doubt on the bill's chances at becoming law before the new year, Capitol Hill newspaper Roll Call reported late last night that the food safety bill will likely be sent back to the Senate because Democrats violated Article 1, Section 7 of the Constitution, which clearly states that revenue-raising provisions originate in the House.
According to Roll Call, Section 107 of S. 510, which allows for the collection of fees, has "ruffled the features of Ways and Means Democrats" who are expected to use a procedure known inside the beltway as "blue slipping" to block the legislation.
"We understand there is a blue slip problem, and we expect the House to assert its rights under the Constitution to be the place where revenue bills begin," a GOP aide told the paper.
If the House blue slips the bill, Senate Democrats would have to use precious floor time to go back through procedural votes to re-introduce an amended version of the bill because Sen. Tom Coburn (R-OK) would, as he did earlier this year, object to a unanimous consent agreement to limit debate on the bill.
Sen. Coburn remains the most outspoken opponent of the legislation, arguing that it does not address systemic problems with federal food safety oversight and is too costly. Coburn introduced a substitute bill on Tuesday that failed in a 36-62 vote.
Originally published on Food Safety News
July 23, 2024
East New York Farms is building food security and providing jobs for its neighborhood.
July 17, 2024
July 2, 2024


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By Chirag Shah, Developer Programs Engineer
Today we are announcing a major milestone for another one of the Google APIs client libraries. The Google APIs Client Library for PHP has officially reached Beta.
This means we're comfortable enough with the stability and features of the library that we'd like you to start building real production applications on top of it and send us your feedback. The library now includes service-specific libraries and samples for several Google APIs, built on our new client library generation infrastructure.
The Google API PHP client supports the following Google APIs right now, with more on the way.
- Buzz API - Sample
- Books API - Sample
- Latitude API - Sample
- Page Speed Online API - Sample
- Tasks API - Sample
- URL Shortener API - Sample
curl "http://google-api-php-client.googlecode.com/files/google-api-php-client-0.4.1.tar.gz" -O tar -xvf google-api-php-client-0.4.1.tar.gz cd google-api-php-client/examples/Here is some sample code that demonstrates how to use the library and the Google Books API to search for and print the titles of free ebooks by Henry David Thoreau:
<?php require_once 'path/to/src/apiClient.php'; require_once 'path/to/src/contrib/apiBooksService.php'; $client = new apiClient(); $client->setApplicationName("My_Books_API_Example"); $service = new apiBooksService($client); $optParams = array('filter' => 'free-ebooks'); $results = $service->volumes->listVolumes('Henry David Thoreau', $optParams); foreach ($results['items'] as $item) { print($item['volumeInfo']['title'] . '<br>'); }Let us know what you think. We would love to hear your feedback and are always happy to help you out on the forums.
Since Google I/O 2010, we've been developing APIs that can provide descriptions of themselves via metadata. This new technique makes it easier to create and maintain client libraries that support more languages, work with more APIs, and are easier to use than ever before. This post announces one of several recent major milestones for our client libraries.
Chirag Shah is a Developer Programs Engineer on the Google+ team.
In his spare time, he enjoys listening to music and contributing to open source projects.
Posted by Scott Knaster, Editor


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IF YOU'VE got your health, then you've got everything. Though slightly condescending, this old saw is as true for machines in process applications as it is for the people that operate them. And, in yet another similarity to human healthcare, recent advances in sensing technologies are allowing users to look ever deeper and with greater resolution into their machines and process applications. This and focused handling of the resulting data is allowing many users to find and diagnose potential problems even sooner, and make more intelligent decisions on scheduling maintenance, allocating resources, managing inventory, and scheduling to minimize the cost of maintenance and repairs.
Organizationally, it's true that machine health monitoring and/or management fits within larger, less tangible concepts, such as condition monitoring, preventive and proactive maintenance, asset and lifecycle management, and even enterprise resource planning. However, machine health comes in far more direct contact with the processes it monitors than any ostensibly higher-level methods, and often helps supply them with data they need to function.
Healthy Evolution
"As users move from straight, time-based or run-to-failure maintenance, they find they need information on the condition of their assets. Next, it's important to integrate that physical, process data into a condition monitoring platform, which can correlate it, and help measure performance," says Scott Breeding, product line leader for Bentley Nevada, a division of GE Energy. "This is what gives users an indication that a bearing may be running hot before they can see any signs of wear or damage. For example, an engineer may use process data indicating a vibration to deduce that a centrifugal pump is cavitating because an operator is applying inadequate suction-head pressure, and this can support a decision to improve that process.
"Process data also can be used to write new rules around assets, derive subsequent indicators, and screen data to produce alerts when a problem may be likely to occur. This allows users to focus more closely on the 'bad actors' in their applications."
An amplitude/phase/time (APHT) plot of vibration data from the drive rollers on the Wisaforest mill's lime kiln shows their motor speeds varying between 991 and 1,083 rpm, and demonstrating a structural resonance at 36 Hz as the kiln moved from low- to higher-speed operation, which required stiffening and strengthening the drives' supports.
For example, Bently Nevada recently implemented its System 1 software, Trendmaster Pro data acquisition hardware and Dynamic Scanning Modules, and 3500 monitoring system and proximity probes on almost 50 process machines at UPM-Kymmene's Wisaforest pulp and kraft/sack paper mill in Pietarsaari, Finland, and reportedly has solved 10 separate machinery problems. This project also was part of the mill's overall installation of a new recovery line to maintain its production of 800,000 air-dried tons per year.
Though most of its machines use rolling-element bearings monitored by accelerometers, the mill's huge lime kiln uses fluid-film bearings monitored by X-Y proximity probes and accelerometer transducers. To let operators see basic condition information data and let rotating machinery engineers see diagnostic data, the mill's process control system set up a bi-directional OPC interface, which imports amplitude and alarms from System 1 into the DCS, and exports process variables from the DCS into the System 1 database. The main problems that Bently Nevada helped solve at the mill included:
- Identifying intermittent, high-frequency vibration amplitudes in the inboard bearing in the recovery boiler's 600-kW air fan, which helped the mill's engineers better schedule lubrication system repairs and bearing replacements.
- Correcting elevated vibration levels in the 15.4 x 443-ft lime kiln's drive rollers by evaluating their phase, rpm, amplitude and frequency data, which found a structural resonance at 36 Hz as the kiln moved from low- to higher-speed operation, and required stiffening and strengthening the drives' supports (See Figure 1).
- Locating a cracked inner ring in a bearing in the recovery boiler's exhaust gas fan, shown by a characteristic "ringing" phenomenon in the amplitude/phase/time (APHT) plot for the fan, which was repaired.
- Identifying excess vibration and a faulty rubber element in a coupling on the recausticizing unit's white liquor pump, which also was repaired.
- Finding inboard bearing deterioration in the recausticizing unit's totally unmonitored mixer, which was adjacent to its monitored rotary filter, and required repairing the mixer's a broken lubrication pipe.
Implementing these solutions reportedly helped the Wisaforest mill achieve payback on its upgrade investment in just eight weeks.
In addition, though basic vibration has been used to check machine health for decades, new algorithms and software are helping users monitor more operating parameters and applications. For example, proximity sensors and software included in Bently Nevada's Asset Condition Monitoring Solution can take signals that indicate the trueness of shafts in motors. "We have new algorithms and software that can set up alerts and alarms based on asset conditions," says Jeff Schnitzer, Bently Nevada's general manager. "We also have Rule Packs that allow users to write rules based on vibration, temperature, or other indicators, and create subsequent functions and responses.
"These and other machine health monitoring capabilities can then be combined with maintenance records, assets classifications, and other data to create baselines for entire plants, and help target future investment where it will return the most improvement. This means no longer touching or replacing components based on past outages and history, but touching or replacing them based on real-time reliability data."
Sharpening Senses
Robert Skeirik, machinery health product manager for Emerson Process Management, says it links the five main senses of machine health—vibration, oil condition, motor current, infrared thermography, and ultrasonics—into its AMS Machinery Health Manager, AMS Suite software, CSI 2130 portable analyzer, CSI 4500 analyzer that connects to a multiplexer, and CSI 9210 machinery health transmitter.
Skeirik adds that Emerson and its CSI division recently helped upgrade the 20% worst-performing of 27 coal pulverizers at American Electric Power's (AEP) John E. Amos plant in St. Albans, W.V. The units were previously serviced on a 12-month schedule, and collectively experienced 3-4 unexpected failures per year. Besides preventing $240,000 worth of breakdowns in the project's first year, CSI and Emerson helped AEP and Amos' engineers achieve savings and return on investment (ROI) in several machinery health monitoring areas:
- Lube oil analysis saved more than $74,039 for a 4-to-1 ROI
- Infrared thermography saved more than $343,000 for a 5-to-1 ROI
- Motor current analysis saved more than $344,000 for a 20-to-1 ROI
- Motor testing saved more than $381,000 for a 20-to-1 ROI
- Leak detection saved more than $1.2 million for a 60-to-1 ROI
- Vibration analysis saved more than $4.2 million for a 42-to-1 ROI
- Total savings of $6.5 million for a 27-to-1 ROI
"Machinery health is now just one component of a plant's overall status, which is continually seeking to answer the plant manager's two basic questions about reliability and availability," says Skeirik.
An Ultrasonic Heartbeat
Though vibration detection and analysis is a bread-and-butter machine health monitoring method, and one that's also increasing in sensitivity and sophistication, some developers believe ultrasonic monitoring may be even more useful. Based on military and aerospace monitoring methods, Stress Wave Analysis (SWAN) technology from Swantech reportedly can detect even earlier when a machine is starting to demonstrate symptoms that will lead to failure (See Figure 2 below).
"Ultrasonic technology provides the earliest detection of machine problems by detecting the unique sounds made by friction, impact events, and minor surface damage," says Ralph Genesi, Swantech's president and CEO. "Traditional machine health has been based on vibration, but this is too late because some damage may already have occurred and a safety shutdown may be needed. Ultrasonic detection gives users more time to gain the knowledge to plan maintenance and a response, and lets users decided if they need to shut down now or if they can safely run their planned quota.
"In addition, electrical signal histories collected over time, or histograms, can show if new signals are skewed, and even help indicate if a machine has lube problems, cracks, or seal damage. Ultrasonics can even show when an external load is placed on a machine, which can help operators change bad habits, and extend the lives of their devices."
For example, to help it process more than 2 million tons of reclaimed steel per year, North Star BlueScope Steel in Delta, Ohio, recently asked Swantech to help maintain its flat roll machines, which usually run 24/7 and can cost $1,000 per minute of unplanned downtime. The steelmaker's SWAN system gathers information from Stress Wave data collectors associated with each bearing, analyzes it on a SWANserver in the plant's offices, reports on any early signs of wear in the mill's equipment, and allows managers to plan maintenance or repairs up to six months in advance.
"We're concerned mainly about failed bearings and failed gears," says Matt Morris, North Star BlueScope's reliability-team leader. "All of the gearing is unique to the machine, and we have no spares. Because getting a new one usually takes at least six months, limping along or shutting down completely can add up to large losses. However, the field of available methods is very narrow because many of our large bearings turn very slowly. Also, the sensors mounted on each bearing have to withstand the high temperatures and heavy vibration in our processes.
"Initially, the SWAN system was standalone, but it was eventually added to our Level 1 network for backup purposes. Now, it's also accessible through routers from our main Level 3 business systems."
Not only has access to this information reduced production losses, but it also has allowed NorthStar to shrink its $3 million inventory of spare parts, and avoid paying thousands of dollars for rush orders.
Networking, Education Needed
While machine health monitoring technologies have made technical advances on their own, they've also been aided by increasingly reliable and widespread networking solutions and protocols. Breeding says developers had been trying to integrate process data for years, but that previous networks weren't durable and secure enough. Now, not only are hardwiring and connectors more robust and less expensive, but fieldbus protocols, such as OPC, Profibus, Foundation fieldbus, and Modbus are becoming more standardized and accepted by end users. Likewise, many former worries about network security have been lessened by the fact that many process industry companies have established virtual private networks (VPNs), and are growing more comfortable about allowing authorized access to them. Also, once any initial network connection is made, it's possible to distribute machine health monitoring data up to the enterprise level, over wireless links, or via the Internet.
Though many increasingly sophisticated technologies are coming into play in machine health monitoring, none can be effective if they simply aren't used. "Many customers think their job is done when they buy a machine health product. Our company found that many users had very nice monitoring technologies suffering from 'dusty keyboard syndrome" because they were still using schedules and weren't relying on condition-based monitoring in their daily routine," says Steve Sabin, editor of GE Energy's Orbit magazine. "Though it started out making instruments, this was why Bentley Nevada started its machine diagnostic services business. Having monitoring instruments was fine, but companies that got the best results were those that trusted their instruments to drive their behavior, and change they way they did their work. In the best plants, 80% of the maintenance work is planned, while 20% is reactive, but this still isn't they way most plant are run."
So, while machine health monitoring is still solidly based on empirical observation, the power of that observation, the focused analysis of the resulting data, and the faster and wider distribution of its results can give user unprecedented benefits, but only if they use them.