It’s hard to imagine where some of these people come from. When you see graffiti on a wall calling to “Make America White Again” or an Alt-Right assembly throw up the Nazi salute, it’s hard to wrap your mind around how someone could become that filled with hate.

What happened? How is it possible that people who started off life as nothing more than children grow into hate-filled, prejudiced human beings?

We like to say that nobody is born racist, but it’s not entirely true. The dark reality is that the seed that grows into racism exists in everyone. Human beings are born predisposed to prejudice. Even if we don’t let that seed grow into hatred, many of us still feel a sense of “otherness” about other races. Whether we want it to or not, it affects the way we interact.

It’s just how our brains are wired. We instinctively sort people into groups, and that sparks a natural psychological process that, if left unchecked, can push us into racism and fear.

And it starts nearly as soon as we are born.

6 months old: racial grouping begins

By the time babies are about six months old, they start grouping people by skin color. Throughout the short lives they’ve lived so far, they’ve been looking at the faces around them. They’ve seen the faces of their parents, their friends, and the people who give them affection. They’ve started putting those faces into a group that, for the rest of their lives, will be a part of their concept of who they are.

At six months, kids start noticing that people’s skin colors are different and reacting to it. Psychologists have found that, when a six-month-old child who has mainly seen white people sees a black person, their brain registers the difference. They have a jolt of attention, thinking, essentially, this is different.

This isn’t necessarily a bad thing, but it’s the start of something bigger. The baby is starting to recognize that people have different races. More to the point, they’re starting to realize what race their parents are, and they’re developing the concept that this is their group. This is their normal – and every other race is something else.

9 months old: racial fear can begin

Not everybody goes through this, but it happens to some people. If a child has a bad experience with a specific race, it can condition them. Just like Pavlov’s dog salivating at the ring of a bell, a child can learn to feel fear when they see a certain race – and that can start at least as young as 9 months, if not earlier.

It took an absolutely horrible experiment to prove this. A psychologist got a 9-month-old boy to fear furry animals by terrifying the boy every time he saw one. He gave him a pet rat and made loud noises when he saw him. As the child grew up, he became conditioned to feel uncontrollably afraid every time he saw anything furry.

The same thing can happen with races. A traumatizing experience with a race can condition a person to feel anxious whenever they see them. A minority child who gets picked on by his classmates, for example, might learn to fear their entire race – and that fear will be ingrained in them for the rest of their lives.

15 months old: awareness of inequality grows

We start to be affected by the way society treats people by the time we’re 15 months old. We start to notice that the world isn’t fair, and it affects the way we think.

In an experiment, researchers passed out toys, sometimes fairly and sometimes unfairly. Their goal was to find out how babies react to unfairness. As they expected, the babies wanted to play with the fair researchers more than the unfair ones. Or, at least they usually did.

When the researchers split the toys down racial lines, something different happened. Now the babies understood the prejudice. They could understand that they got more toys because the researcher had the same skin color as they did, and they accepted it. They were on the same racial team as the researcher, and they wanted to spend more time with them.

The babies, in short, were noticing social inequality. If their race was on top, they didn’t question it. They accepted it and stuck with their own race – because they wanted to reap the benefits.

3 years old: racial preferences begin

Babies start feeling more comfortable with their own racial group by the time they are nine months old. It comes out in the way they see faces. When newborns, babies distinguish every race’s face equally, but at the age of three that starts to change.

Psychologists showed pictures of faces to babies and found that they had more positive reactions to their own race. When they misread an emotion, it was usually to think their own race as “happy” when it wasn’t and to think of other races as “angry” when they weren’t.

This is probably because they connect their own race with their parents. Once they can group races, they start connecting their parent’s race with the positive emotions they feel for them. They draw on their limited experience and conclude that their own race can be counted on to love and care for them – but they still don’t know what to make of people who are different.

5 years old: stereotyping begins

By the time children are five, all these little prejudices have started to grow into full-fledged opinions. They’ve started to accept that they are grouped into races, and now it’s not just an awareness – it’s a worldview.

At five, kids’ experiences and what they’ve heard from their parents have shaped a lot of how they see the world. They can divide people into racial groups and form opinions about what each racial group is like.  

Kids in Israel, for example, think Arabs are completely different from them. In a poll, most Israeli five-year-olds expressed the belief that Jewish boys and Jewish girls have more similar interests than Jewish boys and Arab boys. In other words, they saw racial lines more prominently than they saw gender lines.

That doesn’t happen in every culture. It did in Israel because, there, racial divides can affect everyday life. If kids have been encouraged to stereotype, they will. And they won’t just copy their parents’ views – they’ll take them even further. Because they have limited experiences and are still predisposed to think in simple groups, they see the world through even more of an “us vs. them” lens than adults do.

More than 5 years old: racial anxiety grows

All these fears and prejudices build up, and they start to affect the way people think. Once children have these emotional reactions to other races ingrained in them, they become a part of them. At this point, it’s not just a choice to be racist. It’s a biological reaction.

When people see a race they’re prejudiced against, their bodies naturally release stress hormones. This race is dangerous, they’ve been conditioned to believe, and so their bodies start getting them ready to either fight or run away.

This can have a major impact on the quality of someone’s life. It doesn’t just stop with inequality; it affects every part of life. It’s believed that African Americans are more prone to heart disease because they spend more time feeling racial fear.

The cure

So what are we supposed to do? If our minds naturally build up discomfort and intolerance around other races, how are we supposed to ensure that our kids don’t grow up that way?

The answer is exposure. The more time children – or anyone, really – spends with people from other races, the less they view them as an outsider group. They stop feeling fear or difference and start to accept them.

It changes a lot. People who spend more time with other races have better views of them, have more interracial friendships, and are more likely to fall in love with someone from another race. They’re more open-minded about everything because they start to understand other cultures.

Which means, if we want our kids to have a more peaceful future, we have to integrate. We have to live and raise our children side-by-side. If we do that, when our brains sort us into groups, they’ll put us together with the whole human race.