People who know me fairly well say I'm one of the least judgmental people they know. People who don't know me well think I'm conceited and snobby. As for what I think, I'm very confident and happy with myself but I don't feel like I look down on everyone. If I do it isn't for intellectual reasons.
I have a friend who's boyfriend does the same thing, only he looks down on her because she is sexually experienced. She's tried telling him it makes her feel bad, just not talking about it at all, stuff like that. He seems to just do it anyway. Since your bf is AS, I would just be really straightforward with him...bring it up after he makes one of his comments. Say how it makes you feel, etc. Sometimes I feel like my intellect is the main thing I have going for me and if it's insulted I get offended. If he has other people in his life that do this to him, that may be why he does this to you.
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After a time, you may find that having is not so pleasing a thing, after all, as wanting. It is not logical, but it is often true.
--Spock