'The Dress' Proves We Hate People Different From Us

Last night, the colour of a dress seduced the Internet. Yes, it was a cool optical illusion. Yes, other than Victoria's Secret Swim Special there wasn't much on TV that night. But the real reason the dress continues to captivate our attention is because humans love to form groups based on often trivial similarities.

Once we form these groups, we love to fight with outsiders. People were more interested in pledging allegiance to #teamwhiteandgold or #teamblueandblack than reading about the science behind the photo. So while we now know it's empirically black and blue (the optical illusion has to do with a combination of an overexposed photo and how different brains process colour), the hashtags continue as if the debate can still be won through the wittiest tweet.

I'll admit that when I first saw the dress, I panicked. I saw blue and gold, which clearly meant I was a color blind castaway who would spend my life alone mistaking apples for oranges. It wasn't until a few others agreed with my Facebook status that I took a deep breath. I had found my people.

Our tendency to group ourselves with those who are like-minded or like-sighted is harmless when it comes to a dress (far as I know, nobody's been killed yet). But on a larger scale, the psychological phenomenon has serious implications.

Humans form their social identities based on groups that range from book clubs to besties. We prefer people who share our beliefs and appearance, which is why many friend groups and couples look so homogenous. While psychologically those who resemble us provide a feeling of safety, the side effect is often discrimination.

When someone doesn't fit our in-group, we push them away. Take job hiring, for example. If the interviewer is wearing your college class ring, you'll probably chest-bump instead of shake hands. But if you're an immigrant applying to work at a North American company, your reception will likely be more frosty.

A recent study by University of Toronto professors titled "Why do some employers prefer to interview Matthew, but not Samir?" found those with Chinese, Indian or Pakistani names were on average 40 per cent less likely to be interviewed than those with English-sounding names. When a man living in the U.S. changed the name on his resume from José to Joe Zamora, his inbox was suddenly flooded with responses.

When someone is part of an out-group, we exaggerate their differences. Politics provide a case in point. Even though we often support party leaders based on superficial information such as appearance and demeanour (I once wrote one of the reasons I like Barack Obama is because he also likes arugula), Republicans and Democrats are more polarized now than they've ever been in the last two decades. The worst part is that we're often unable to extend empathy towards those with different political views. A recent This American Life episode called "Red State Blue State" told stories of friendships ripped apart because one person called the other a socialist for supporting Obama. And our supposed inability to relate to those who differ from us has an effect on policy.

The richest people are often those who do not support social equality. Nicholas Kristof wrote in The New York Times about how "among Democratic politicians, personal wealth is a predictor of supporting legislation that would increase inequality." He also found the wealthiest Americans gave less to charity as a fraction of income than the poorest.

Too many of us assume the homeless are fundamentally different from us and therefore not worthy of our help. I've written before about how almost a quarter of Canadians think people living on streets are to blame for their circumstances, and almost a fifth think their tragic flaw is laziness. In reality, reasons beyond their control such as mental illness, family problems, and traumatic brain injuries are main factors.

The human desire to sort ourselves into like-minded groups is an instinct we should be critical of. That doesn't mean bringing someone who hates reading to your book club, or atheists to church. A community filled with people who hold your beliefs is an extremely valuable thing. But when the group mentality turns into a game of us versus them, the result can be more devastating than a spat over a dress.