I read a lot of history, and lately that’s been a lot of prehistory. You know, stuff that existed before writing, since academics officially regard history as analysis of text. What I’m now reading isn’t exactly that, it’s The Knowledge. It’s a literal manual for rebuilding the world after a futuristic collapse. In a way it’s the opposite direction to what I’ve been studying: Off in the future. But just like every post-apocalyptic story, part of the fun and the point is to see regress to our primitive state. The past and the future intersect.

At least on the face of it the book is a literal manual for how to rebuild civilization after some great collapse, be it meteor strike, nuclear war, or epidemic. But I don’t think the author believes in an impending collapse and isn’t a so-called “Prepper” who prepares for the end times. At least he seems to think it’s not very likely in the very near term. How likely should we think a global catastrophe is?

Here’s a very not-data-based answer that is correspondingly not very precise. It depends on the time frame and the size of the class of events we call “global catastrophe”. If we say 200 years is the time frame and catastrophe can include most of the world (but not, say, Africa and Australia) being in a nuclear shoot-out, or the avian flu depopulating the world by 10%, then … I’d say the odds of such an event are “good”. Especially given that global warming seems inevitable and disastrous, I think we can lump that in with a slow-burning global catastrophe, making some degree of catastrophe pretty near certain. But if we call the catastrophe, by definition, something that happens suddenly one day in the next few decades, and leaves no corner of the Earth unaffected (and definitely destroys New York because it’s not yet a global disaster if you don’t get a half-sunked Statue of LIberty) … I’d put the odds near zero.

Back to the point, although the book on its face is about The Fall and rebuilding, I think that’s largely just a fun and interesting conduit to re-conceive of modern technology. It gives an excuse to remember that the Serbian army besieged the city of Gorazde. The people inside built little turbines and placed them in a river, fixed to a bridge, to generate electricity. It reminds us that, if the survivors of The Fall did not take care to collect the seeds of domesticated crops, they would quickly lose in the competition with weeds and die out—and humanity would have to spend an extra several thousand years re-domesticating new or old species. It is a reminder of how much technology was necessary to build the modern world. So much of it is so deep in the background that we need it threatened or removed before we can see it again.