Usaully when someone is being sarcastic, there is a certain tone to their voice that they get. It can be best described as a smart ass tone...kinda cocky and like something that stepped out of a james dean movie but not quite that extreeme. Pay attention to their tone of voice and you might start to notice it. Also if it sounds like BS or otherwise unlikely, assume that it is unless proven otherwise. In high school, there were these guys that would say stuff like there is more than one way to get pregnant...Out of curoisity, I said How is that? He said by a BJ, I found that hard to believe, but my thinking was that maybe science has proven something...so I said, Really? And of course then I was the object of ridicule. So stuff like that...Just ignore.
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All art is a kind of confession, more or less oblique. All artists, if they are to survive, are forced, at last, to tell the whole story; to vomit the anguish up.
-James Baldwin