Yes but like you said, "you [need to] already have some necessary rationality to do this"- that's the kind of thing i'm talking about. You can't buy that original rationality and you can't buy the fact that rationality exists. The stuff you said is true but I think you are trying to answer to different topic than which it is relevant to. Money can buy things and make you happy- but money can't buy the fact that happy exists. When I talk about "money can't buy everything", it's in that way that i'm talking about (not to be confused as saying 'owning things doesn't make you happy').