No one, not even a ‘friend,’ can make us better. But it is a great happiness in life to meet a person of quite different construction, different bent, completely dissimilar views who, while always remaining himself and in no wise echoing us nor currying favor with us (as sometimes happens) and not trying to insinuate his soul (and an insincere soul at that!) into our psyche, into our muddle, into our tangle, would stand as a firm wall, as a check to our follies and our irrationalities, which every human being has. Friendship lies in contradiction and not in agreement! Verily, God granted me Strakhov as a teacher and my friendship with him, my feelings for him were ever a kind of firm wall on which I felt I could always lean, or rather rest. And it won’t let you fall, and it gives warmth.
Much relevance here to relationships more then friendship.