To the degree that we're unconscious of our own biases, we block our connections with others. And trust me, if we possess a brain, we are biased. We make conclusions and judgments based on what we've seen and heard in the past, a human capability that both protects us and constricts us. It protects us so that we consciously decide, perhaps, not to walk alone at night in certain areas of the Bronx wearing our best diamonds. It constricts us when we unconsciously decide that we would rather not sit next to a person who looks like he's from an inner city on the metro - especially not if he's dressed differently and has a different skin tone than us.
I get it, we are afraid of awkwardness and not knowing what to say to someone who is different from us and then embarrassing ourselves. There's also the chance that the person will be a maniac or think we are more interested in him than we really are and get the wrong idea. He might also just not understand what we are saying due to language and dialect barriers. But we won't know unless we get out of our comfort zones once in a while and try.
Maybe it's up to us to make it a practice in our lives to learn how to ask the right questions. To learn about the lives of people who are different from us, and find out what's important to them. To learn about the unique struggles they may deal with on a daily basis. To expand our awareness beyond what we know and encounter regularly, into a different life. And to even "try on" the experience of a person completely different from us, and yet, probably similar in many ways as well.
The true essence of a human requires looking much deeper than surfaces to find what binds us. Sometimes we dig deeper and then decide we don't like what we see, and so we stop digging and move on to someone else. However, there is always an unending well of more to see and learn from each individual. The question is, how deep are you willing to look?