Thread by @JohnBarnesSF

The model you're vaguely remembering is actually an explanation for Kondratiev waves; it assumes they exist, which is far from demonstrated and may not be for many decades (data quality being what data quality is).

https://twitter.com/MorlockP/status/1306237522910031875

It's sometimes called the Deployment Shelf or the Shelf of Possibilities. The idea, which you can recognize from either Keynes or Hayek, is that most of the time investors are cowardly AF and avoid risk as much as they can, so as inventors and entrepreneurs tinker and get ...

... things working, but then no one is going to run the risk of investing to "deploy" them into the economy -- not while there are safe investments around instead. So all these tech possibilities accumulate on the metaphorical shelf ready to deploy. Meanwhile the pure research...

... types go right on finding anomalies and puzzles that require more money to test experimentally than any foundation or lab will give them. So there's another shelf up above the Waiting for Low Interest Rates shelf, the Waiting for Research Money shelf. Upper shelf science...

... lower shelf more or less ready to go tech. And most of the time there's a few decades of each on both shelves. Then something shakes the shelf: typically a really major depression, or a prolonged war between rich countries, or both. Another Keynes/Hayek shared view, now ...

... fully conventional: the rate of profit on a mature technology will gradually fall to zero, and (Keynes) money basically trickles up faster than it trickles down. So after a while you have a liquidity trap: there's no investment as safe as just holding cash and waiting ...

... for deflation to make the cash worth more. And at that point, people who absolutely have to have profits start taking a lot of bad bets -- a.k.a. the tech on the shelf. (Alternative: or nations try out tech on the shelf because the war otherwise seems to head for costly...

... stalemate). And, sonofagun, some of it works, and some of what works interacts with other stuff that works, and there's a new tech revolution underway, and suddenly advanced tech looks like a great investment. Swarm of briefly emboldened investors descend on market ...

... begging to get into things, and the ones who are most emboldened start to think that they don't want to miss the next big thing (or if it's a war, that some wonder weapons are just over the horizon)...and money pours into basic research, a few wild hypotheses are finally ...

... confirmed, discoveries that just needed a little push to get made fall off the top science shelf and into the now eagerly deploying tech shelf ... and that's where the "magic" new tech comes from.

Of course, Hayek & Keynes & Schumpeter now all back together:now there are...

... abundant safe investments available for the next generation, so innovations begin to sit on the shelf and accumulate there, while we all do the Long Boom Square Dance of exploiting that recent big deployment. Till it's time again, maybe 100-160 years later, for the ...

... Crazy Ass Swing Dance Innovation Boogie.

Kondratiev himself, btw, being a pretty conventional Marxist, just thought it was crises of overproduction resolved by abandonment/deterioration of older facilities, and nothing to do with tech at all.

And there are many other takes on it, including the one I think most likely: periodicity in a borderline chaotic system.

BUT. I didn't end up an economist. I was a sci fi writer. And the Deployment Shelf, whatever its dubious merits for economic forecasting ....

... tends to predict a whole big gob of wild and crazy tech innovation and sensawunda inducing stuff just over the generational horizon, which is to say, it's one great idea generator for moderately-squishy through technothriller-hard SF. And so I have used it a lot.

(Probably Resuming Hiatus here unless one of you says something so damned interesting I can't stop myself. Please do not feel obligated to try).

Captain Spaulding Syndrome strikes (there's some who call me schnorrer, hurray hurray hurray): the original article referenced is "How to Build a Future." List of the many places it has been reprinted at isfdb.org/cgi-bin/title.…. I no longer have it in any electronic form.

Also most of it is now wildly out of date, since it is more than thirty years old. So please don't use it to create fiction nowadays -- if you want a how to article on mathematical future building, catch up on your reading, practice your math and coding, and write a better one!