Sounds pretty reasonable, doesn't it?
I think so. And there were other reasons, too, for Aristotle's theory of the four elements to look more appealing than the atomism he was rejecting. For example, it attempted to explain hot and cold by incorporating them as basic qualities of the elements and giving some rules about how one can turn into the other. Taking hot vs cold and dry vs wet as the basic qualities, we have four possibilities:
Transitions between these four that change only one quality are easy and more common (like water->air by evaporation, or air->water by rain), while those that change both qualities (air<-->earth, fire<-->water) are harder, next to impossible. This actually corresponds to observed phenomena to some degree. The atomic theory had nothing of the kind and didn't even attempt to account for things like temperature.
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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