This seems to be imagining some other much bigger kind of collapse than what the thread started with. The top post proposed an EM event that knocks out computer

This seems to be imagining some other much bigger kind of collapse than what the thread started with. The top post proposed an EM event that knocks out computers, which is not something that destroys all books and mechanical machines, nor kills any people immediately. I don’t necessarily buy the energy argument. Why would it have to be coal & oil primarily? Maybe it doesn’t. Coal and oil aren’t gone, but there’s also ample solar, wind and hydro to power a new society. Would losing computers actually cease coal & oil production completely? I kinda doubt that. I’m sure it would be a temporary setback and slow things down, but there was a lot of coal and oil production before computers. The hypothetical question here seemed to already assume that food production and energy aren’t gone, it was just whether we can rebuild electrical compute without computers, based on knowledge of mechanical compute. We can certainly imagine some epic worst-case scenario where no people with knowledge of any engineering survives, no books survive, and future humans have to start from absolute scratch. That seems far less likely than the probability that some of our knowledge carries. But even in the total doomsday scenario, what we have already is evidence that it worked the first time, and yes we can imagine hypotheticals that make it harder, but we already survived stories of dragons once, right? The default assumption kinda has to be that it might happen again given time.