> In the enlightenment you could make discoveries about lightning with a kite and a key, in your free time when you weren't working as a publisher or founding America.
And yet those discoveries weren't made in the previous thousands of years during which people had been standing around in thunderstorms. The enlightenment represented a paradigm shift where a new innovation - the scientific method - was applied en masse for the first time and it led to revolutions in science, technology, and society. Whenever a paradigm shift happens, be it the practical steam engine or long range electricity transmission, you invariably have a lot of suddenly accessible low hanging fruit. The mid 20th century had a surprisingly large number of such paradigm shifting innovations such as solid state transistors, integrated circuits, jet engines, nuclear reactors, antibiotics, solar cells, the internet, lasers, credit cards, the list goes on. Entire new fields of science and sectors of industry popped up in a very short period of time.
We continue to innovate, but our innovations are mostly evolutionary and there have been comparatively few paradigm altering inventions in the past 30 years, especially when one considers how much larger the population of sufficiently educated and affluent individuals who could produce such innovations has become and how much easier it is for such innovations to be communicated. It is impressive how good we've gotten at picking higher fruit, but we should still be asking why we are struggling so hard to find low hanging fruit.