Lukeprog's post didn't ask "how could they have discovered this through means other than with what modern science discovered it". Instead, it said "these discoveries follow from a few basic first principles and they could have just thought about them, but didn't"
We were both wrong; here's the relevant part:
The ancient atomists reasoned their way from first principles to materialism and atomic theory before Socrates began his life's work of making people look stupid in the marketplace of Athens. Why didn't they discover natural selection, too? After all, natural selection follows necessarily from heritability, variation, and selection, and the Greeks had plenty of evidence for all three pieces. Natural selection is obvious once you understand it, but it took us a long time to discover it.
So, the Greeks had evidence for some intermediary conclusions, and it is asserted that they could have worked their way from there to a good understanding of natural selection. Not necessarily using first principles to help discover natural selection.
You haven't said why natural selection wouldn't follow from those things listed (although saying why it would is the OP's responsibility), or that the Greeks didn't have enough evidence for those things. Instead, you addressed the possibility of going from those to a good understanding of natural selection, arguing that "...to even formulate that hypothesis...requires..." and you listed things that the historical human discoverers actually required to get it, when the issue is the minimum it should have required.
But your response is an appeal to incredulity that puts far too much weight on what led people to discover evolution to convincingly address whether or not a different way was possible. Showing that a set of things was sufficient doesn't show they were necessary.
As the OP thought the argument from "heritability, variation, and selection" to natural selection strong enough to be implicit, you should argue for a reason to believe he would have falsely believe that before dismissing the idea. Without that, all we have is a clash of intuitions, and on your part it doesn't look like you've updated much on lukeprog's apparent extreme confidence that it could have been so derived (which I infer from his unfortunate failure to argue for the point).
Also see: History of the Friendly AI concept.
The ancient atomists reasoned their way from first principles to materialism and atomic theory before Socrates began his life's work of making people look stupid in the marketplace of Athens. Why didn't they discover natural selection, too? After all, natural selection follows necessarily from heritability, variation, and selection, and the Greeks had plenty of evidence for all three pieces. Natural selection is obvious once you understand it, but it took us a long time to discover it.
I get the same vibe from intelligence explosion. The hypothesis wasn't stated clearly until 1965, but in hindsight it seems obvious. (Michael Vassar once told me that once he became a physicalist he said "Oh! Intelligence explosion!" Except of course he didn't know the term "intelligence explosion." And he was probably exaggerating.)
Intelligence explosion follows from physicalism and scientific progress and not much else. Since materialists had to believe that human intelligence resulted from the operation of mechanical systems located in the human body, they could have realized that scientists would eventually come to understand these systems so long as scientific progress continued. (Herophilos and Erasistratus were already mapping which nerves and veins did what back in the 4th century B.C.)
And once human intelligence is understood, it can be improved upon, and this improvement in intelligence can be used to improve intelligence even further. And the ancient Greeks certainly had good evidence that there was plenty of room above us when it came to intelligence.
The major hang-up for predicting intelligence explosion may have been the the inability to imagine that this intelligence-engineering could leave the limitations of the human skull and move to a speedier, more dependable and scalable substrate. And that's why Good's paper had to wait until the age of the computer.
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