I have argued in earlier blogs and in my book The Most Important Book, that significant innovation does not occur in societies with a powerful hereditary elite class.
I figured this out by seeing that the Industrial-technical revolution in the 19th Century occurred because the oldest primogeniture son was left in England while the innovative siblings, driven by trade, were sent out to England's colonies. The same phenomenon was visible in the greatest land of innovation, America, because the elite remained on the East Coast as the innovative siblings moved to the Great Western expanse for commerce.
But the strongest argument for this reality of innovation comes from China.
Over two millennia China swung from multiple separate states back to national dynasties. During that time the people in China created some of the most important technical innovations on the planet. But only two came into common use. What was invented in China?
My main source is Joseph Needham's multi-volume work on the subject. The Chinese invented the compass, gunpowder, white paper, movable type, two stage rockets, matches, piston pumps, the wheelbarrow, the astronomical clock tower observatory, the escapement mechanism on clocks, and much more. The two that came into common use were the silk loom and porcelain. Both related to the invention of lacquer used for waterproofing.
It has been argued that knowledge of these innovations was limited to a few small areas. This is easily disproved because encyclopedias of technology were in use throughout two millennia in China. Encyclopedias that covered the geography and technology of the entire State were published and circulated at regular intervals.
One encyclopedia was so vast that it included 11,000 volumes, completed in 1408, called the Yongle Encyclopedia. I saw a tiny fragment of the small fragment that has survived, in a special room of the Library of Congress. It had detailed maps and illustrations of local technology. Most of this great encyclopedia was destroyed recently by Mao's rampant Communist revolution.
Was the elite in China so powerful that is could suppress innovation? The best example is what happened to Zheng He's great naval fleet of 250 ships that traveled in the 1420's to all the major ports in the South China Sea and the Indian Ocean, including the Arabian peninsula and all of East Africa. One emperor, Hongxi stopped it all. The fleet was too costly at a time when Mongols were buffeting the inland borders. The Zheng He fleet was dispatched to show Chinese power and collect tribute. The motivation for the fleet was not wealth and trade because trade was left to the merchant class, a low tier in the Chinese hierarchy.
Admiral Zheng He did bring back exotic toys and novelties for the Emperor.
Which takes us to the next evidence of Chinese hereditary elite suppression of innovation.
David Landes in his masterpiece on the history of clocks found that many of the earliest clocks were brought to China as novelties to entertain the Emperor. They got no further.
Clocks were a central part of the Industrial Revolution because they allowed the European class of merchants to conduct trade at scheduled times for socially equal traders. In China, all meetings were based on social hierarchy and the lower person waited until the higher person arrived. No clocks were needed. The merchant class was not important.
I think China is the proof, over two millennia, that an hereditary elite class that benefits from stasis in the society is the most important form of suppression for innovation.