Socrates knocked off boys??

He's talking about the ancient Greek practice of pederasty. However, I don't think that we should imagine that Mickey Sachs would have a particularly detailed knowledge of current scholarship on the subject. It is clearly supposed to be a casual remark made for humorous effect. Mickey would know something about pederasty from his general knowledge, but as he isn't a professional classical scholar I don't think we should imagine that he is making a historical judgement abut Socrates (it seems to be well attested that Socrates was sexually attracted to boys/younger men, but that, unusually for a man in his position, he did not engage in sexual relations with them). In fact, Mickey cannot actually have read anything by Socrates, as none of Socrates' writings are extant. He must mean that he has read accounts of Socrates in other ancient writers. What he is really saying is, "I have read some ancient Greek philosophy, and I am aware that ancient Greek philosophers practiced pederasty, for which reason I doubt the utility of their philosophy." That would not, however, have been as funny, and would not have sounded like something which Mickey would actually have said. I really doubt that Woody Allen intended us to think this seriously about it. As I say, you have to look at the character who says the words, and in this case I don't think we should read very much into it. If Frederick had made this comment, on the other hand, I think that we would be right to think more seriously about it, as he would seem to be the sort of person who quite possibly had read Kenneth Dover's Greek Homosexuality when it came out in 1978, which would presumably have been about seven years before Woody Allen was making the film.