One persons secret and their comments about it struck a cord with me. "I do not like people who remind me of myself." While I do not relate to that secret, Terry Gross (I think it was Terry, anyway) said, "Like not wanting to join any club that would accept you."
That comment struck me in that while Idon't feel exactly that way, I do think I would shy away from a club with more than one of me. I like the idea of being unique. I have no idea how unique I actually am, but I enjoy the illusion. If I met someone just like me that illusion would be shattered.