From the Rolling Stone interview, via TPM:
Have you ever read Ayn Rand?
What do you think Paul Ryan's obsession with her work would mean if he were vice president?
[OBAMA] Well, you'd have to ask Paul Ryan what that means to him. Ayn Rand is one of those things that a lot of us, when we were 17 or 18 and feeling misunderstood, we'd pick up. Then, as we get older, we realize that a world in which we're only thinking about ourselves and not thinking about anybody else, in which we're considering the entire project of developing ourselves as more important than our relationships to other people and making sure that everybody else has opportunity – that that's a pretty narrow vision. It's not one that, I think, describes what's best in America. Unfortunately, it does seem as if sometimes that vision of a "you're on your own" society has consumed a big chunk of the Republican Party.