The Stone Age professor

Some time ago, I was puzzled about the apparent overcapacity of the human brain. Why should a human of 10-20,000 B.C. have been potentially as smart as modern man, despite not needing to do much more than pick fruit and stab pigs ? Thanks to this excellent piece, I now feel a lot more comfortable about why early humans had the capacity to solve differential equations but didn't :

1. You don't need to be a great hunter to have an evolutionary advantage. You just need some small advantage over prey and be able to out-compete other animals - not necessarily by much, but a bit. So the very first users of technology didn't have to start out as potential Einsteins. They just had to be able to throw rocks at things and have a good chance of success.
2. To actually become a great hunter, you do need an incredibly high mental capacity. The article goes into detail about just how frickin' complex manufacturing some of the seemingly primitive early tools can be, especially in specialist environments. You don't need to be able to understand Maxwell's equations to chuck a rock at a warthog, but if you want to make a bow and arrow... well, you're getting close. Damn close.
3. There are more evolutionary advantages to being a great hunter than just the ability to collect food and not die. Really good hunters may have breeding advantages, thus adding in sexual selection pressure to the innate risks associated with running away from sabre-tooth cats (as if early man didn't have enough to worry about). So there's a clear route as to why the modest advantage of being a decent hunter, with the capability to survive but not thrive, should lead to very much cleverer people.
4. Early humans may have had the capacity to develop into people as smart as us, but probably generally didn't - because nutrition may play an important role in developing brains. So our ancestors may have been just as conscious and self-aware as us, and generally comparable in intelligence, but they may not have ever produced the equivalent of Newton or Da Vinci.
5. Some discoveries evolved through collective cultural luck. The article notes that even starting a fire from basic materials is extremely difficult for modern people if they're unprepared and untrained, as well as many other examples where knowledge can really only be gained through trial and error (there's no way it would ever occur to anyone, no matter how smart, that to get the maximum benefit from corn you have to soak it in a solution containing ground-up seashells : that simply can't be derived from first principles). As the population slowly grew, the probability of beneficial chance discoveries also grew. The capacity for language and human ability for social learning (which the article says is much greater than for any other species of ape) meant that there was little chance of backsliding.

I still wonder at exactly what point human brains reached the potential to become as advanced as they are today, but collectively I think the above points can at last solve the puzzle to my satisfaction.

The last point about luck is more important than you might expect. Aeon had a very nice piece about how choosing randomly (e.g. through divination or whatever) can be advantageous, because although it doesn't lead to better reasoning, it does help reduce bad reasoning. This article takes that much further. Being random can make you unpredictable, which is sometimes advantageous. But far more importantly :

Hunter-gatherers really want to learn the essentials of their hunter-gatherer lifestyle, and learning it is really hard. Their heuristics are: Learn from people who are good at things and/or widely-respected. People will fear and obey authority figures like kings and chieftains, but they give a different kind of respect (“prestige”) to people who seem good at things. And since it’s hard to figure out who’s good at things (can a non-musician who wants to start learning music tell the difference between a merely good performer and one of the world’s best?) most people use the heuristic of respecting the people who other people respect. Once you identify someone as respect-worthy, you strongly consider copying them in, well, everything.

Understanding why people are doing what they are can be extremely difficult, but understanding that what they're going is successful is much easier. And often (especially back in prehistory), not even the "experts" really knew why they were doing what they were doing, so you couldn't just ask them. They stumbled on solutions by chance and preserved them through tradition and ritual. This meant that not questioning them made a lot of sense, especially in cases where the detrimental effects weren't immediately obvious :

Now consider what might result if a self-reliant Tukanoan mother decided to drop any seemingly unnecessary steps from the processing of her bitter manioc. She might critically examine the procedure handed down to her from earlier generations and conclude that the goal of the procedure is to remove the bitter taste. She might then experiment with alternative procedures by dropping some of the more labor-intensive or time-consuming steps. She’d find that with a shorter and much less labor-intensive process, she could remove the bitter taste. Adopting this easier protocol, she would have more time for other activities, like caring for her children. Of course, years or decades later her family would begin to develop the symptoms of chronic cyanide poisoning.

Which leads to a paradoxical situation : we evolved the capacity for reason, but it can be self-destructive. Being conservative stops us from messing with things we don't understand.

Rationalists always wonder: how come people aren’t more rational? How come you can prove a thousand times, using Facts and Logic, that something is stupid, and yet people will still keep doing it? Henrich hints at an answer: for basically all of history, using reason would get you killed. A reasonable person would have figured out there was no way for oracle-bones to accurately predict the future. They would have abandoned divination, failed at hunting, and maybe died of starvation.

A reasonable person would have asked why everyone was wasting so much time preparing manioc. When told “Because that’s how we’ve always done it”, they would have been unsatisfied with that answer. They would have done some experiments, and found that a simpler process of boiling it worked just as well. They would have saved lots of time, maybe converted all their friends to the new and easier method. Twenty years later, they would have gotten sick and died, in a way so causally distant from their decision to change manioc processing methods that nobody would ever have been able to link the two together.

So what do we do about it ? How do we preserve the vital conservative element that protects us whilst allowing the carefree experimentation that drives genuine progress ? Eliminating small-c conservatism isn't an option : even in the far future, we're going to need to stop children from poking around in the warp reactor...

Book Review: The Secret Of Our Success

I. "Culture is the secret of humanity's success" sounds like the most vapid possible thesis. The Secret Of Our Success by anthropologist Joseph Henrich manages to be an amazing book anyway. Henrich wants to debunk (or at least clarify) a popular view where humans succeeded because of our raw intelligence.