This explosion of growth we are seeing is relatively recent, and is due not only to advances in technology, but also to cultural changes which may perhaps have been more important to enable this relentless expansion.

What was the most recognized traditional means to become rich if not by pillaging and military conquest? The idea that you could (and should!) become rich by individual economic effort was not common at all. To the contrary, it was frequently taken to be immoral, like the Medieval condemnation of usury, or the ostracism of rich people in Ancient Greece.