Every year, Microsoft founder Bill Gates drafts a letter charting the course for the foundation he created with his wife, Melinda. This year, the focus is on the value of precise measurement in driving innovation and progress. His inspiration was the book The Most Powerful Idea in the World, “a brilliant chronicle by William Rosen of the many innovations it took to harness steam power.”
Certainly mensuration was important to the development of the steam engine, but there was a much more crucial ingredient, and unless we understand the role that it played, solutions to the world’s most pernicious problems will remain elusive. The key to grasping this missing ingredient is the aeolipile. As shown in the accompanying video, the aeolipile is a hollow metal reservoir with multiple radial “exhaust pipes,” all of whose spouts point off tangentially from the hub. To make it work, you simply suspend it, fill it with water, and light a candle under it. And… Voila! You’ve harnessed steam power to generate rotary motion.
This device is also known as Hero’s Engine, after Hero of Alexandria—who invented it over two thousand years ago…. Despite its seemingly obvious practical applications, Hero’s Engine was never more than a party favor. It had not the slightest impact on the course of human history. Why not?
The ultimate causes are contentious (Deirdre McCloskey will give you one answer), but the proximate one is obvious: the aeolipile was never commercialized. There wasn’t a sufficient network of entrepreneurs and investors toiling away in ancient Alexandria to relentlessly seek out, capitalize, and commercialize new technologies and innovations. The steam engine was refined and widely deployed during the Industrial Revolution only because such an entrepreneurial network had come into existence by the late 18th century, first in England and soon thereafter, elsewhere.
And that’s the real key to massively disseminating the benefits of innovation: enlisting the assistance of the free enterprise system. It is not a coincidence that the productivity of elementary and secondary education has collapsed while productivity in virtually every other field has steadily improved. Education has been largely excluded from the free enterprise system for the past 150 years.
So, while precise measurement certainly has its role to play, I hope someday to read an annual letter from Bill Gates that focuses on the need to harness all the freedoms and incentives of the marketplace for the betterment of education the world over.