A week ago I went to a cognitive science conference in Chongqing, where I gave a talk called “A Theory of Human Evolution and Application to Education” (a theme of the conference was education). A sponsor of the conference, a magazine called Scientific Chinese, will publish short versions of the talks. Here is the short version of my talk, only a little different than what I’ve said before but far more compact.
Humans specialize. We make a living thousands of ways. A dentist makes a living one way, a carpenter another, and so on. No other species does this. In every other species, all members of the species make a living in one or two ways. All sparrows search for and eat the same food, for example. I propose that human nature changed in several ways to make possible our extreme within-species specialization.
It started with hobbies. Hands, evolved to swing through trees, could also make tools. Tools saved time. They made it easier to hunt and prepare food. Hobbies were a good use of the spare time. It was better to do one thing repeatedly during your spare time (and become skilled at it) rather than do many different things. Because of this advantage, an across-day tendency to repeat (to do today what you did yesterday) evolved. This tendency not only caused hobbies, it also caused diversity of hobbies. It was hard to change hobbies, so choice of hobby became less sensitive to feedback (the payoff from doing the hobby). Today, this tendency to repeat across days causes procrastination. It is hard to start a job-like activity. Procrastination is so common and hard to avoid because the underlying tendency was so important.
Diverse hobbies led to trade. I give you what I make, you give me what you make.
Language began because it increased trade. It helped the two sides of a trade find each other. It started with single words. Single words made it easier to convey what you wanted: You said the word for it. They also made it easier to indicate what you made: You said the word for it. Someone else could say the word for what you made and point at you. The first conversation: Person 1: X? Person 2: X (pointing). English family names reflect this usage; many come from occupations. For example, smith means metal worker.
A healthy economy has three features: 1. Many goods and services. Diverse hobbies provided this. 2. Easy trade. Language provided this. 3. Innovation. A healthy economy creates new goods and services. This was encouraged by the evolution of desires for (a) current tools made better than necessary and (b) useless “tools”.
Demand for current tools made better than necessary came from the evolution of several tendencies. These tendencies produced behavior that is still common. First, gift-giving. Gifts are better-made versions of ordinary things. The “improvements” — the differences between the gift version and the ordinary version, such as a nicer package — are useless in the sense that neither giver nor recipient would buy the gift version for themselves. Second, holidays, festivals, and ceremonies. Holidays, festivals, and ceremonies create demand for fancy versions of ordinary things, such as special clothes, tools, and foods. For example, Japanese tea ceremonies use special tools and require special clothes. Third, connoisseurs, collectors, and souvenirs. Connoisseurs notice small improvements that most people don’t notice and pay for them. Collectors buy things that non-collectors would not buy or at least pay more for them. A collector of frog-related things might buy an eraser in the shape of a frog. Making an eraser look like a frog does not make it erase better. Souvenirs are usually ordinary objects (ashtray, pen, key chain) made more desirable. Souvenirs make anyone a collector.
The existence of gift-giving, holidays, and so on increased demand for finely-made things — better versions of ordinary things. Finely-made things were harder to make than ordinary things, so this demand pushed artisans to become more skilled. The more skilled an artisan, the more easily he could innovate. A skilled baker is more likely to invent a useful new bread than an unskilled baker.
The useless “tools” that promoted innovation are art, decoration, and music. Desire for art and decoration supported the development of new techniques and materials — new paints, for example. Music encouraged technical advances because better control of materials allowed you to make better-sounding musical instruments. The tendency behind fashion (year-to-year changes in preferences, and a desire for novelty) pushed artists and artisans to continue to innovate, to continue to develop new techniques and materials. They could benefit from innovating, but only for a limited time.
Art, decoration, and music allowed the development of revolutionary technologies — technologies that weren’t refined versions of old technologies. Can you invent metal by refining stone tools? No, you can’t. Endless trial-and-error while making stone tools will teach you how to make stone tools that are suitable for gifts, but it will never lead to metals. To produce something as different from its predecessors as a metal tool, you need to reward small steps on the way to getting there. This is what art does. Metal looks good. Long before our ancestors could make useful tools with metal (tools that could outperform existing tools), they could make art with metal.
The application to education is that this tendency to specialize in terms of job must be strong within us. The members of a group lived in the same place and had similar genes, yet there must have been powerful forces pushing them toward different jobs. Today these forces push students in different directions. The closer they get to being old enough to work, the more powerful these forces probably become, the more diversity they create. One reason I developed this theory is the diversity I saw in my own students. Within one undergraduate class, all psychology majors, I realized there were big differences between students. After graduation, they would choose different jobs.
Most teachers ignore these differences. They treat all students alike. It is like trying to put shoes of different shapes and sizes into identical boxes. Most shoes won’t fit, no matter what box you use. Teachers who treat all students alike are fighting human nature. I learned to take advantage of the diversity of my students by giving them great choice. When I gave them enough choice, they found activities they really wanted to do. They did them enthusiastically and learned a lot. With human nature on my side, teaching became much easier.