Harry Potter and the Methods of Rationality

The reason why this was crazy was that only one person in the tribe had to invent a tool, and then everyone else would use it, and it would spread to other tribes, and still be used by their descendants a hundred years later. That was great from the perspective of scientific progress, but in evolutionary terms, it meant that the person who invented something didn't have much of a fitness advantage, didn't have all that many more children than everyone else. Only relative fitness advantages could increase the relative frequency of a gene in the population, and drive some lonely mutation to the point where it was universal and everyone had it. And brilliant inventions just weren't common enough to provide the sort of consistent selection pressure it took to promote a mutation. It was a natural guess, if you looked at humans with their guns and tanks and nuclear weapons and compared them to chimpanzees, that the intelligence was there to make the technology. A natural guess, but wrong.

Before people had quite understood how evolution worked, they'd gone around thinking crazy ideas like the climate changed, and tribes had to migrate, and people had to become smarter in order to solve all the novel problems.

But human beings had four times the brain size of a chimpanzee. 20% of a human's metabolic energy went into feeding the brain. Humans were ridiculously smarter than any other species. That sort of thing didn't happen because the environment stepped up the difficulty of its problems a little. Then the organisms would just get a little smarter to solve them. Ending up with that gigantic outsized brain must have taken some sort of runaway evolutionary process, something that would push and push without limits.

And today's scientists had a pretty good guess at what that runaway evolutionary process had been.

Harry had once read a famous book called Chimpanzee Politics. The book had described how an adult chimpanzee named Luit had confronted the aging alpha, Yeroen, with the help of a young, recently matured chimpanzee named Nikkie. Nikkie had not intervened directly in the fights between Luit and Yeroen, but had prevented Yeroen's other supporters in the tribe from coming to his aid, distracting them whenever a confrontation developed between Luit and Yeroen. And in time Luit had won, and become the new alpha, with Nikkie as the second most powerful...

...though it hadn't taken very long after that for Nikkie to form an alliance with the defeated Yeroen, overthrow Luit, and become the new new alpha.

It really made you appreciate what millions of years of hominids trying to outwit each other - an evolutionary arms race without limit - had led to in the way of increased mental capacity.

'Cause, y'know, a human would have totally seen that one coming.

And beside Harry, Draco walked along, suppressing his smile as he thought about his revenge.

Someday, maybe in years but someday, Harry Potter would learn just what it meant to underestimate a Malfoy.

Draco had awakened as a scientist in a single day. Harry had said that wasn't supposed to happen for months.

But of course if you were a Malfoy, you would be a more powerful scientist than anyone who wasn't.

So Draco would learn all of Harry Potter's methods of rationality, and then when the time was ripe -

Chapter 25: Hold Off on Proposing Solutions

To seek out new life, and J. K. Rowling!

Note: Since the science in this story is usually all correct, I include a warning that in Ch. 22-25 Harry overlooks many possibilities, the most important of which is that there are lots of magical genes but they're all on one chromosome (which wouldn't happen naturally, but the chromosome might have been engineered). In this case, the inheritance pattern would be Mendelian, but the magical chromosome could still be degraded by chromosomal crossover with its nonmagical homologue. (Harry has read about Mendel and chromosomes in science history books, but he hasn't studied enough actual genetics to know about chromosomal crossover. Hey, he's only eleven.) However, although a modern science journal would find a lot more nits to pick, everything Harry presents as strong evidence is in fact strong evidence - the other possibilities are improbable.

Act 2:

(The sun shone brilliantly into the Great Hall from the enchanted sky-ceiling above, illuminating the students as though they sat beneath the naked sky, gleaming from their plates and bowls, as, refreshed by a night's sleep, they inhaled breakfast in preparation for whatever plans they'd made for their Sunday.)

So. There was only one thing that made you a wizard.