Human nature (and it’s pretty clear that we do have a nature) is complex and multifaceted. We have multiple tendencies, biases, and heuristics all operating at once, pulling us in different directions. These tendencies also interact with our culture and environment, so we are not a slave to our biases. We can understand and rise above them, and we can develop norms, culture, and institutions to nurture our better aspects and mitigate our dark side. That is basically civilization in a nutshell.

In fact, many scientists believe that humans also domesticated themselves – applied selection pressures that favored people who were less aggressive, more pro-social. It’s hard to prove this is true, but it does make sense. As civilization took hold, people whose temperament were better suited to that civilization would have a survival advantage.

Psychologists, however, have long documented that pro-social behavior in humans is a double-edged sword, because we only appear to be pro-social toward our perceived in-group. Toward those who we believe to be members of an out-group the cognitive algorithm flips. This is referred to as in-group bias, and also as “tribalism” (not meant as a knock against any traditional tribal culture). Negativity toward a perceived out-group can be extreme, even to the point of dehumanizing out-group members – depriving them of their basic humanity, and therefore any moral obligation to them. That appears to be how our brains reconcile these conflicting impulses. Evolutionary forces favored people who had a sense of justice, fairness, and compassion, but also needed a way to suspend these emotions when our group was fighting for its survival against a rival group. At least those groups with the most intense in-group loyalty, and the ability to brutalize members of an outgroup, were the ones that survived and are therefore our ancestors.

Increasingly neuroscience can investigate the neuroanatomical correlates of psychologically documented phenomena. In other words, psychologists show how people behave, and then neuroscientists can investigate what’s happening in the brain when they behave that way. A recent study looks at one possible neural mechanism for in-group bias. They recruited male subjects from the same university and then imaged their brain activity while they retaliated in a game against targets from their university and targets from a rival university. The researchers used rival universities, rather than more deeply held group identities (such as nationality, race, religion, political affiliation) to avoid undue stress on the subjects. Yet even with what they considered to be a mild group identity, the subjects showed greater activity in the ventral striatum when retaliating against out-group targets than in-group targets.

They focused on the striatum because this part of the brain is involved in reward circuitry, which is a powerful determinant of human behavior. Therefore it seems that aggression or retaliation toward a member of an out-group is more rewarding than the same activity against a member of our in-group – it makes us feel good. This is not surprising, and was predicted by the researchers, because it fits with the notion that there is a real in-group cognitive bias.

What does all of this mean for human society? Obviously this is way beyond the scope of one blog post, but here are some thoughts. First, as always, it’s important to recognize that in-group bias exists. That is the first step in being able to overcome it. Different groups vying for survival through aggression and violence is not a desirable option in our modern world (with all the modern weapons and nukes and everything). Violent conflict is also inefficient, wasteful, and diverts resources from more productive activity. We also need to recognize that in-group bias is universal – it is not just of feature of other people or other groups (even if it may seem that way). For example, it’s very tempting to conclude that the other political faction is rife with in-group bias (such as the Republican tendency to celebrate “owning the libs”) but the evidence shows that in-group bias is not limited to any political faction.

So if we acknowledge that in-group bias is a deep and universal part of human nature, what do we do about it? One method is to orient our thinking toward the notion that our in-group is humanity. That is one of the complexities of the in-group bias in our modern world – what constitutes a group? Back when we lived in relatively isolated communities, it was fairly obvious what our group was – it was likely your entire world. As civilization developed, however, groups became larger and more complex. A community became a region, then a nation, then an alliance. There are groups within groups within groups, and there are identities that are entirely orthogonal to each other. People who all identity with the same nationality may also divide into groups based upon their religion.

From one perspective, therefore, we can simply continue this trend toward identifying with larger and larger groups and extend our in-group to humanity. This is the ultimate expression of globalism. If everyone does what’s best for the planet and for the human population as a whole, everyone will be better off. Yes this is idealistic, but it’s good to have ideals to strive for, even if they are unrealistic (at least for now). Also, as I said, group identities are multiple, overlapping, and complex.  I can consider myself culturally a New Englander, while still identifying as an American patriot, and also supporting the faction of free liberal democracies around the word while rooting for all of humanity to succeed.

What this means in practice is that we never give in to the darkest temptation of in-group psychology – coming to believe emotionally that members of an out-group are subhuman. Unfortunately, this remains common. Perhaps the most dramatic historical example is the Nazi campaign against the Jews. They spent years pushing propaganda that portrayed Jews as literal vermin. This mindset is necessary if you are going to brutally murder six million people. It may be psychologically impossible (at least without severe emotional harm) to do that to someone you emotionally feel is a fellow human being (unless you are a psychopath). Thinking of the enemy as not human is really freeing. That is why there is a movie/video game trope that you can kill with abandon five types of enemies – insects, zombies, monsters, robots, and Nazis. It’s profoundly ironic that “Nazis” have, in a way, been dehumanized as generic villains. They are really just an iconic stand-in for “evil villain drones”, like the stormtroopers from Star Wars.

Another method to tame our in-group bias is through cultural norms, laws, and institutions. Such things provide a balance to our counterproductive psychological tendencies. For example, I am a member of a profession that has a very intense professional standard of behavior and ethics. These standards are drummed into us during training, we are given forceful feedback if we deviate from these standards, and if we persist it will negatively affect our careers. Once in practice these standards are enforced by healthcare institutions like hospitals, professional organizations, licensing bodies, insurance companies, and legally through the threat of malpractice suits. This system is not perfect, of course, but the goal is to achieve the highest standard possible of professional behavior, in many cases by overriding our emotional instincts and biases.

Democracy is another institution that seeks to quell in-group bias. This, I think, is why many people are concerned about the current political situation in the US. The balance between partisan politics on one side and a dedication to the country as a whole, the institution of democracy, and the Constitution on the other, seems out of whack. The system only works when everyone plays by the rules, especially when we are on the losing side (that’s when it really counts). However, in-group biases seem to be peaking. This is partly due to the fact that it is increasingly easy to game human psychology by pushing the buttons of in-group bias. Partisan outlets literally demonize the other side, and we are all seeking that reward hit by retaliating against the others, who are somehow less than human (seen as partisan drones, not real people). This is obviously a much more complex issue, but in-group bias is sitting right in the middle of it, grinning menacingly.

In-group bias is a reality of the human condition. Understanding it is critical. As individuals we need to be vigilant against it and expand our thinking so as to rise above it. Collectively we need to bolster the institutions that temper our in-group bias and allow us to work and live effectively together.