Another way to put it is accelerating returns. It's the inevitable consequence of having a generation of tools being used to create the next generation. Rinse and repeat thousands of times. Individual technologies follow an S-curve. The whole follows a similar curve. Human civilization was in the initial relatively flat stage since the invention of the first tools until the industrial revolution. Only the invention of agriculture caused things to pick up a little because civilizations had to get serious about things like astronomy and mathematics to create accurate calendars. We are now in the stage where the curve is getting steeper so fast that you can feel it as the years pass by. What the world will be like in 100 years is beyond our imagination.