We are all tribal. We don’t have a choice. We are designed that way. Our architects—our genes—design us to be biased toward fellow members of our tribe as opposed to members of other tribes. Genecists are even identifying the genes that do the designing.

We might compare ourselves to felines and canines. Felines are generally loners. The only social life they enjoy is the occasional mating. They have their fling, then return to their solitary lives.

Canines, on the other hand, have active social lives. Wolves, typically, live in packs. All members of the pack help to raise the young, even the males. They hunt as a unit. They have intense loyalty to their pack. and only to their pack, not to wolves generally. If a strange wolf enters their territory, threatening to exploit their resources, they may drive it out, even kill it.

We are like wolves, a social animal, loyal to our pack, or tribe, not necessarily hostile to members of other tribes, unless we perceive a threat, and then we can be as vicious as wolves.

This genetic bias in favour of our own is essential to our humanity. Without it we wouldn’t be the social animals we are. We wouldn’t love our families, feel an obligation to our community, commit to our faith or our political philosophy or our profession, be patriotic, or cheer for our local hockey team. We would be, like the felines, solitary creatures.

All this is very good stuff. How we relate to others is very much what being human is all about. This is what brings us our greatest joys (and sorrows). Without it, we wouldn’t be human in a recognizable form.

But there is a dark side.

Throughout most of humans 300,000 or so years on the planet, our tribe was a simple thing, a small homogeneous group of no more than a few dozen members. We shared spiritual beliefs and customs generally, men all did one job, women another. But beginning about 6,000 years ago, this began to change until today we live in vast, heterogenous societies with millions of members.

We belong to myriad tribes: our clan, our community, our country, our religion, our profession, our political party, and on and on. And we entertain loyalties, or biases, to all of them. Our genes have dictated it be so.

This means we continually face the possibility of tension not only with societies outside of our own, but even to members of our own society who belong to a different group than we do. People of another class, another political persuasion, another religion, another ethnic group, another race. If we perceive a threat to our own group, whether it be real or imagined, the possibility of hostility arises. Intrinsic bias makes us friends and it makes us enemies. Particularly the latter, perhaps. As Daniel Kahneman points out in Thinking, Fast and Slow “Bad impressions and bad stereotypes are quicker to form and more resistant to disconfirmation than good ones.”

Sometimes little harm is done. Supporting different sports teams is generally just harmless fun, and competing between different companies can be economically stimulating. But when hostilities arise between political or religious or racial tribes, things can turn nasty.

You can reinforce your tribe by celebrating what the members have in common, or you can reinforce it by emphasizing how you differ from another group, favourably of course, a tempting but often dangerous strategy. This is the strategy of demagogues, religious bigots and racists.

There are those to whom allegiance to their tribe is more important than their allegiance to society generally. To these groups hostility is of little concern and may even be welcomed. They are inclined to believe their tribe—political, religious, racial—is so superior it deserves to be privileged and even, perhaps, to dominate society.

Such groups have exercised insidious influence to the point of tearing societies apart. They can be devilishly clever at exploiting vulnerabilities such as disaffected masses. What is currently happening in the United States serves as an example. The only protection is healthy institutions: an equitable economy, a strong social justice system, and a vigorous democracy. Societies need to keep their institutions in good repair.

Individuals, too, need to remind themselves from time to time that we are all intrinsically biased toward our various tribes. No exceptions. By being aware you can prevent your bias from corrupting your relationships with members of other groups. If you are in a position of power, such as a police officer, it is doubly important.

You cannot, of course, live your life in a state of eternal vigilance. The best most of us can do is recognize situations in which prejudice can be serious and take care to nullify bias. But it will always be there, safeguarding your tribe.