The Reverend Thomas Robert Malthus published “An Essay on the Principle of Population,” in which he discovered and explained an oscillation (he called it “vibration”) between periods of high income and a small population, and, conversely, periods of low income and a large population. These oscillations characterized the entire Middle Ages, from 1200 to 1800. Then, the first Industrial Revolution, capitalism, progress, nation states that listened to the will of the people, and the consciousness of the people, changed everything, and began a centuries-long period of monotonous growth in both income and population.
