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So here's a quick setup: One or two calamities hit as once. No one is spared and every nation on earth is effected by it. Soon the population dwindles to roughly the same number as the 1800's which is 1 billion. Could such a drop put us back so far that we actually forget how to maintain and build technology. Could cars one day be re-purposed and if so how long would it take?


marked as duplicate by Rekesoft, bilbo_pingouin, Gryphon, Cyn, JBH Jan 17 at 15:46

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    $\begingroup$ Regression to a technological level below mid-19th century is very hard to believe. There are simply too many books describing how to make simple engines and industrial machines, there are simply too many people who know how to make them, there are simply too many tools around. Mankind may forget how to make microprocessors, but mankind cannot forget how to make steel and steam engines. And you cannot possibly actually mean "forget how to maintain and build technology": stone-age people had technology. Stone age technology is technology. $\endgroup$ – AlexP Jan 17 at 2:34
  • $\begingroup$ The premise seems flawed: If the growth of industrial and technical knowledge was a function of population, then the Industrial Revolution would have happened in China first...and centuries earlier. If loss of population led to loss of technology, then areas hard hit by the Bubonic Plague(s) should have experienced technological regression until the population recovered...but did not. $\endgroup$ – user535733 Jan 17 at 3:23
  • $\begingroup$ There are two points of view on this subject, both argued here on worldbuilding - optimistic and pessimistic. Optimistic maintains that civilization and its knowledge is very resilient, and it would take an extinction level event to bring us down to stone age. Pessimistic point to a very high interdependency of modern technology, so that relatively small disruption would produce a "domino effect", leading to substantial global regress. $\endgroup$ – Alexander Jan 17 at 4:13

At a population of 1 billion, it is unlikely. Rebuilding the infrastructure may take a few years depending on the nature of the calamities, but data is so redundant now that even if 90% of the world's data farms, local servers, and books were destroyed, our tech would still be mostly preserved in one place or another, and we'd still have enough people to maintain the economic diversity required to build and maintain it. The more likely outcome would be that the progress of tech would just be dramatically slowed down because of fewer people to innovate.

You'd probably need to reduce the human population by another 1 or 2 orders of magnitude to really cause a pre-industrial regression.


It's not possible that people would forget how to make and maintain all modern tech. There are just too many technical books out there; nothing that leaves a billion humans alive could destroy them all.

But it IS possible that, although they would remember how to make modern technology, they would be unable to do so. Consider the fact that we have used up all the easiest-to-access resources, particularly fossil fuels. If these calamities cause society to collapse, once it reforms it will have great difficulty re-industrializing. This is because energy will now be hundreds or thousands of times more expensive. Some places might be able to rebuild hydro-electric plants, but that's just not an option for most of the world.

It wouldn't be exactly pre-industrial; some modern tech would survive. Medicine, for instance, would still be far-superior than pre-industrial medicine. Just the knowledge of germ theory would make an incredible difference, let alone knowledge about nutrition, surgery.

So basically, the world would know how to make modern tech, but it would be logistically impossible.

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    $\begingroup$ "We have used up all the easiest-to-access resources, particularly fossil fuels:" where is this idea coming from? There is plenty of coal available (and even in Europe, let alone in Australia), there is plenty of iron ore available (and even in Europe, let alone elsewhere). You may even have noticed that the price of petroleum is so low that major exporters like Arabia and Russia are becoming desperate. $\endgroup$ – AlexP Jan 17 at 3:12
  • $\begingroup$ Yes, those resource all still exist. In deep, relatively poor deposits. How long do you think people could keep giant mining equipment, like a Bagger 288 (en.wikipedia.org/wiki/Bagger_288) running without industrial support? How long could they keep oil refineries running? $\endgroup$ – Ryan_L Jan 17 at 4:14
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    $\begingroup$ You are severely misinformed. And the equipment you mention is used for surface mining; on the very Wikipedia page is picture showing how such equipment is used. Not that deep... $\endgroup$ – AlexP Jan 17 at 5:59
  • $\begingroup$ It's pretty deep. Remember, before mining began at that site there would have been quite a bit of soil overburden in the way. Look at the panorama picture in the wiki article. See that tan plateau in the background on the left? That's the natural ground level. Notice that it's about as tall as the shovel at the bottom of the pit. The Bagger 288 is 96m tall. Good luck removing 96m of overburdern without modern heavy equipment. $\endgroup$ – Ryan_L Jan 17 at 6:44
  • $\begingroup$ Also remember that this is fiction, this doesn't necessarily need to be true in the real world, but OP can say it is true in the world that he is writing about. $\endgroup$ – Josh Jan 17 at 8:11

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