I disagree. I think that if you are open minded it does not matter if your social circle is different than you. It is a bias in our minds placed there by the society that we have been raised in. Notice how children will play with whomever until society interjects and tells them that they should play with others like them. I am the same height and my best friend as a child was the complete opposite, 6'2 and twice my size. We were best friends because we did not care what others thought about us.