system
Given the following post, respond as if you're commenting on Reddit:
human
What's the difference between an argument and an explanation? Homework Help

I know that this question was already asked (2 years ago), but I couldn't understand the explanation. I tried to google it as well, which led to me only becoming more perplexed. 

I read that an argument can answer the question "How do you know?" while an explanation answers the question "Why is that so?" But I'm struggling to notice the difference. 

For example (from my homework, which we are being asked to determine if what is written is an argument or not, and if it is to standardize it): 
"I don't care what you say. I really think that Mary is in love with Allan. Why? Because she always wants to talk about him. And she gets very excited when he is due for a visit. She even blushes when you ask her about him."

I initially assumed it was an argument, but it doesn't seem to have a logical flow, it just seems to be answering why the speaker believes in what they believe. 

Sorry if this was long. Thank you.
gpt
An argument gives an account as to *how you know* a conclusion to be true, while an explanation gives account as to *why* a conclusion is true. From your example, it is clear that the narrator is giving an account as to how he “knows” that Mary is in love with Allan. He argues that since Mary always wants to talk about Allan, gets excited about him and even blushes around him, she must truly be in love with Allan. But ask yourself are those truly reasons *why* Mary is in love with him? Surely these facts about Mary are a result of her being in love, not what’s causing her to be in love. Therefore, these aren’t explanations as to why Mary loves him. It’s an argument as to how the narrator is justified in believing that she does.