Nope. And that is why I am hesitant about this whole thing.
I asked him right off the bat if he was married, and he said yes. I asked him if his wife would be upset if she knew (he had had a FWB for a about a year, a couple years ago?) and he said yes, most likely.
So he has cheated on his wife, and would again. I'm willing to hear him out about his situation and then decide if it's worth pursuing a relationship (or whatever) with him, but at this point I don't feel that he has enough to offer to make it worthwhile to me and the possibility of hurting his wife is an issue to me.
I enjoy spending time with him and talking about nerdy science stuff, so that's satisfying to me for now.