It seems almost incredible to me that he would not have applied his prime mover idea to a temporal regress of efficient causes. To me here in the 21st century, that seems like such an obvious extension of the same logic, but of course my thinking has been shaped by those who came after Aristotle. I wonder how just knowing that the force from the hand travels down the stick to the stone at a finite speed (the speed of sound in the material) would have altered his conclusions. I don’t think it would weaken his core prime mover argument, but the fact that every transmission of movement from one object to another is also a sequence of events in time would have to have some effect on it. Might it have been more in line with Aquinas’s first cause? There’s probably no definitive answer, but it’s interesting to contemplate.
Yes, it’s interesting to speculate how Aristotle would react—and how his system would change, if at all—if he were familiar with modern science generally speaking.
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