I've been watching the documentary series Mankind: The Story of All of Us on History Channel and a common theme is how disaster opens up opportunity.
It's a historical fact that technology bursts tend to coincide with catastrophes. The Black Death birthed the Renaissance and the World Wars both fueled the modern age. Even the great Classical philosophers, Plato, Socrates and Aristotle did their work against the backdrop of the Peloponnesian Wars.
To me, the Black Death is really the example which illustrates it, partly because it's fairly well documented but still far enough back to have lost some of its immediate visceral impact. A bacteria wiped out almost half of Europe and China's populations. That's a significant portion of the world population.
Before the plague, there was a lot of available manpower. Those in power were able to sit securely on the backs of the masses because there were always replacements available if your peasants got uppity. There was no need to be efficient or inventive, they had a system which worked (more or less).
My theory is that people are essentially lazy. We're capable of bursts of brilliance but it's just too much work to do that every single day.
When the population crashed, all of a sudden the tables turned. Have someone productive and loyal? Better be good to them because there aren't replacements waiting in the wings. Skilled craftspeople became more valued because of their rarity. Whole chains of knowlege were lost as people died without passing on their craft secrets to their heirs. The idea of writing things down gained new importance ... and so did the associated skill of reading.
People needed to figure out ways of doing things with less manpower. Those who could engineer and invent suddenly found themselves in great demand.
Disaster created opportunity and opened up new realms of thought and experience. Literally, in the case of Spain and Columbus. Without the catastrophe of the Black Death, the medieval world would have continued in its strangehold for the foreseeable future.
There's a certain fatalistic comfort in this way of thinking. Stock markets may crash, civilization as we know it may crumble ... but maybe it will eventually open the way to something better.