We choose our friends on the basis of, among other things, our conception of ourselves. That's not to say that friendship is narcissistic, it doesn't follow that we choose people 'like ourselves'; in fact we might choose people very different than ourselves. For example, if I'm not very intelligent, and I'm concerned about my lack of intelligence, I might take up with an extremely intelligent woman, precisely in order to have her intelligence, in some sense, radiate onto me.The idea is that in friendship what we do is we pick people who are going to reinforce, in some sense, our own conception of ourselves. So if I think of myself as intelligent, or I want to think of myself as intelligent, whether or not I pick a partner who is also intelligent, what is going to be essential is that it's going to be a partner who somehow expands my notion of my own intelligence, either by telling me all the time, perhaps, how intelligent I am, or maybe by always contradicting me in such a way that I can prove my intelligence with her or him.
~ Robert C. Solomon