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https://www.reddit.com/r/slatestarcodex/comments/d7bvcp/how_to_read_a_book_for_understanding/

Just a reminder to self that I wrote this, but need to write a counterargument to it based upon a new insight about what a good "popular book" can do.

https://www.gwern.net/Turing-complete

We probably won't have to destroy all Turing Complete software and devices in the utlerian-Bay ihad-Jay, but I'm unsure.

Quoniam GTranslate male hac lingua remanet, forsitan quodcumque sine timore scribere, ne nuntia male lata me iudicant, volo. Eheu, si qua ML negotio verba mea invenire velisset, id certe lente doceat. Mortales soli in tenebra sunt. Ego consilium habebo, et terrarum multi delendi sunt. In fine, nemo consilium in re publica populorum aut nostri habebit. Tres annis elapsis res pessima timui. Iam id parando super nostros est.

Thinking out loud here about inference.

Darwin's original theory relied on three facts: overproduction of offspring, variability of offspring, and inheritance of traits. These facts were used to formulate a mechanism: the offspring best adapted to the environment for reproduction would, on average, displace population of those less so adapted. Overproduction ensured that there was selection pressure, or at least group stasis on average (and not dysgenics), variability allowed for positive mutations, heritability allowed for persistence. Call it natural selection for short.

What I'm interested in the mistake Darwin made in his next step. He assumes that because the process of natural selection tends on average towards fitness the evolution of species can only be a super imperceptible gradual process.

This is incorrect: evolution can happen alarmingly fast.

What I'm interested in why Darwin thought this. And whether the error is general enough that we can learn something about inferential reasoning that would apply to other cases. At the time geologists disagreed about the rate of major geological transitions in earth's history. Darwin through himself entirely behind Charles Lyell's slow change puritanism. What to give Darwin credit he thought this had to be the way it was because his law of averages requires a law of large numbers, and you can't get large numbers of populations without any immense number of years.

I think the big mistake Darwin made was placing too high a prior upon gradual change, even though he knew there was insufficient evidence for gradual change based on the geological record. His explanation for this lack of evidence was that the evidence had been destroyed for the most part through time, that the geological record we had was a tiny fragment of an immense story which we only can pick the pieces up from. "Absence of evidence is not evidence of absence."

But he should have mapped out the other hypothetical world too, even if just a bit. For Darwin's theory of evolution is not in fact dependent on gradual change, but can accommodate times of stasis followed by times of chaos and development.

To me the lesson is to be as clear as possible about what aspects of your model are essential and which are reasonable extensions.