ACT I
Scene 1
When did the Homo sapiens species begin?
If you invented a time machine, how far back in time could you go to adopt a baby and bring them back to the present day, and raise them as a normal member of society?
On the surface that’s a simple question. The answer is 50,000 years ago. But think about how much that really tells us about human intelligence.
The first behaviorally modern humans had our level of intelligence because they had all the brain components we do. That also means we haven’t evolved any new brain components in 50,000 years. That means the only real difference between us and people who lived 50,000 years ago is that we’ve had 50,000 years to think of new ideas.
The reason we’ve been able to think of all these new ideas is because our ancestors evolved so much capacity for abstract thinking. But at the same time, their brains also evolved to deal directly with things in their environments that affected them.
So how much of what we think of as good ideas today aren’t really the best decisions we could make, but they feel like the best decisions to us because our brains are better prepared for thinking about some ideas than they are for thinking about others?
How much more can we understand about human behavior by thinking of the modern world as the stone age + 50,000 years?
Scene 2
That’s the third first principle of evolutionary psychology. All human mental activity evolved in or before the stone age.
This gets confusing to many people. History is the part of our past that got written down. Archeology is the part of our past that didn’t get written down.
It’s easier to tell stories about the parts of our past that got written down. People have been telling those stories for thousands of years.
For many people, hearing about written history first, and hearing so much about it, makes them feel that written history happened first and the stone age was added on later. That makes them feel that our oldest written stories are the most important part of our origins, and our archeological origins are just an idea scientists had.
Scene 3
Have you ever wondered how baby birds learn to fly?
When they jump off their nests and into the air, what happens if they don’t figure out how to fly right away? Do they just fall to the ground and die?
That’s what would happen to you. If you got in an airplane and tried to guess how to fly it, you’d crash it right away. But flying for birds is like walking for you. By the time birds’ bodies are developed enough for them to start flying, their brains are developed enough to understand the basics of how flying works.
If you go to flight school you learn about this stuff. In aviation psychology you learn about something called sensory illusions. As a pilot, you have to learn consciously how to do what birds do intuitively. That includes learning all the ways that your monkey and stone age intuition about motion can make you misinterpret how flying works. Because any one of those misinterpretations can lead you to make a mistake and crash.
The first and biggest sensory illusion is the idea that flying must be easy, because birds fly and people are smarter than birds. But look at a picture of the cockpit of an airplane. You know what all those gauges are for? Each one of them tells the pilot something that’s happening to the airplane that they need to know. Then they have to know how to put all that information together to be able to make the plane fly safely.
If you try to guess how to fly a plane but you don’t know what all those gauges mean, you already don’t know what you’re doing.
Birds don’t have to look at gauges to be able to fly. Most of the time they don’t even have to process all that information consciously. Birds feel all that stuff intuitively.
So far we’re only talking about the differences we feel between walking and climbing versus flying. So how do things like that happen when it comes to big things, like living your life?
ACT II
Scene 1
Some things affected our ancestors much more than they affect us so we overreact to how those things affect us.
People’s strange fear of snakes and spiders is one of those. Our ancestors lived around poisonous snakes and spiders for so long that everyone who wasn’t naturally wary of them died young. We’re all descended from people who were cautious enough around snakes and spiders that they lived long enough to have children— and to pass down their genes that made them cautious around snakes and spiders.
Our survival instincts are highly focused on those specific threats, even though they aren’t as big of threats anymore.
Scene 2
Other things affected our ancestors less than they affect us, or not at all, so we under-react to them.
Most people like food that has salt, sugar, fat, and cholesterol in it. But if you eat too much of any of those things they can kill you. We have a junk food industry that sells us that stuff, and people buy it and eat it, even though it’s not healthy.
We do need some of each of those things to be healthy. On the plains of Africa there was some of that stuff. People ate them whenever they got the chance, and that kept them healthy. But there was never so much that people could eat too much.
That means our ancestors evolved to like that stuff and eat it whenever they could. But they didn’t evolve an off switch for wanting to eat those things. Now we’ve figured out how to mass produce food we want to eat.
Now people want to eat salt, sugar, fat, and cholesterol whenever they get the chance, and they get the chance all the time. So we end up producing and eating a lot of food that isn’t healthy for us.
ACT III
Scene 1
Emotions have physiological effects on us. Those give us clues about how people’s emotions affect their decisions.
Anger sends a lot of blood to your arms and hands to help you hit things.
Feeling like you’re prepared to do something makes doing it feel like a good idea. Does that mean you should hit people whenever you’re angry? Or does that mean you should think harder about what you’re going to do?
Scene 2
Why does fear make you feel cold?
It sends a lot of blood from your head, arms, and torso to your legs to help you run.
When you sneak up on someone and surprise them, why do they open their eyes and mouth so wide?
Opening your eyes like that helps you see. Opening your mouth helps you breathe, because if you need to fight or run, you’re going to need air.
If you see a lion walking around loose, that’s a good time to run away or hide.
If you see someone holding a gun and staring at you as if they hate you, that’s a good time to run away or hide.
But if you go to school and you’re surprised to find out you have a big test that you forgot to study for, and you’re afraid you’re going to fail, does that mean you can escape from it by running out of the room or hiding under your desk?
Scene 3
What do you do when you feel disgusted?
You flare your nostrils, constrict your throat, and lose your appetite. What does that help you do?
It helps you detect which direction a bad smell is coming from and makes you not want to eat anything.
There are many things that can make us feel disgusted. The ones that affected our ancestors the longest are ones that could poison us, either because they’re stagnant water, rotten food, or something that could contaminate our water or food.
But bad smells aren’t the only things that disgust us. We’ve evolved to use that reaction to anything else we want to get rid of, because psychologically it’s still a pretty good reaction to those things.
If you flare your nostrils, gag, and lose your appetite whenever you think about your ex-boyfriend or ex-girlfriend, it means you feel they’re similar enough to rotten food that the same reaction is a good way to deal with the situation. Breaking up and throwing up can have a lot in common, if you feel like you’re getting rid of something that’s nothing but bad for you.
On the other hand, you have to be careful how disgusted you get with other people, because getting rid of people you feel are no good at all is also how murder and genocide happen.
ACT IV
Scene 1
Other psychological illusions are a lot more complicated.
What do you think about landscaping? Wherever people get the choice to make a piece of land feel like a nice place to be, why do they keep thinking of flat ground with grass growing on it? If they can they add a few shade trees and some water. Why do people all over the world keep making the same landscaping decisions?
Well guess what the plains of Africa look like. They’re flat ground with grass growing on it. The best places for our ancestors to live were near some trees and water.
With every lawn, city park, and field, we’re recreating the environment our species evolved in. Every species is attracted to its own environment, because we’ve all evolved to recognize the things we need to survive and reproduce. It’s like we’re all carrying around the same photograph of home in our subconsciousness.
But this works against us in other ways.
Why does deforestation happen? Part of it happens because people who live near forests feel very strongly that replacing the forest with a field— meaning a grassland—is going to make their lives better.
ACT V
Scene 1
How many people can you say you know well?
When people take the time to actually write down a list, they usually get a number between 100 and 200. Those numbers keep showing up wherever people try to cooperate with each other.
Businesses and military units are naturally cohesive as long as they stay below 150 people because everyone gets to know everyone else well enough that their social instincts keep the group functioning. When groups get bigger than 150 people, they start depending on formalized structures and rules to make them function, because people have to start interacting with people they don’t know well enough to know if they can depend on, or how much, or for what.
Scene 2
Well guess what. Stone age people today do the same thing. When villages get bigger than 150 people they either split in two or they have to develop some kind of formalized structure to keep people cooperating with each other.
All the other primates have limits on how big their groups get before they split in two also. Those numbers correspond to the food production of the environment. Primate groups split up around the time they start running out of food.
Our maximum number of about 150 is bigger than for any other species of primate. That tells us that as our ancestors got smarter their tools helped them increase their food production. That let their groups get bigger.
That contributed to the evolution of our intelligence because it made the group-related selection pressures stronger. The more people there were in the group, the more people there were thinking of ways to use tools, the more people had to think about what other people were thinking about, and the more people there were to communicate with. But around 150 they either reached the limits on their food production even with their tools, or reached the limits on how much smarter they could get, so their groups split up.
Scene 3
This is where in groups and out groups come from.
The people you trust the most are the people you feel you can depend on the most. That makes them more valuable to you than other people.
From there it’s easy to jump to the conclusion that the people in your group make better decisions than anyone else, because they make decisions that benefit you more than anyone else does.
That makes you think they’re smarter and more moral than other people, because you think they’re better at doing the right things than anyone else. That leads to racism, nationalism, and anything else where people like the people in their group and distrust or hate people outside their group.
ACT VI
Scene 1
Steven Pinker is a leading spokesperson for evolutionary psychology. He’s written nine books about it so far. They’re all different ways of fitting pieces of puzzles like these together to see big pictures.
Scene 2
The biggest, and most complicated patterns of human behavior are ones where we combine our abstract thinking with our stone age instincts. Every step of the way people make decisions that feel like they make sense, but they have those feelings for different reasons.
How did religion begin? People asked big questions about life and then made
the best decisions
they could think of
in the situations
they were in
for themselves
and the people
and things
they cared about
in their search for answers.
How did people shift from hunting and gathering their food to farming? People made
the best decisions
they could think of
in the situations
they were in
for themselves
and the people
and things
they cared about.
in their food production
And so on, for the development of metal working, which brought the stone age to an end, the development of writing, which began our written history, and everything else people have done where we’ve built up ideas and had effects on the world that make life different from the way it was 50,000 years ago. Whether we make good decisions or bad decisions.
Scene 3
Sensory illusions lead all the way up to people feeling like humans can’t be causing climate change.
A million years ago, when humans domesticated fire, it gave them light, and heat for warming themselves and cooking food, and a good way to ward off predators.
Fires also gave off greenhouse gasses back then. But a few million people on the entire planet lighting camp fires every night didn’t throw off the carbon cycle of the world.
The domestication of fire was an important step along our path of using our abstract thinking and stone age instincts to invent things. Today, because of all those inventions, there are many more people in the world making many more and much bigger fires, because we’ve found many more ways to use light and heat to make our lives easier.
Scene 4
To bring it all together, people use their memory, imagination, and communication to find the best ways they can to live and have families, and all the ideas we think of that way originate with ideas people had 50,000 years ago.
All of it leads back to perception. Everyone always making what they perceive to be
the best decisions
they can think of
in the situations
they’re in
for themselves
and the people
and things
they care about
means that people making better decisions depends on them learning better information.
That’s what education is for.
