Lecture 34: Long Trends—Rates of Innovation
irrigation systems, and avoiding excessive taxation. Military and strategic
factors encouraged rulers to undertake large projects that often encouraged
trade and commerce. In the Roman Empire, military needs stimulated
innovation in road building, bridge building, the construction of aqueducts,
and the building of elaborate military catapults and siege engines. Such
innovations had signi¿ cant “trickle-down” effects. Joel Mokyr writes, “The
Rome of 100 A.D. had better paved streets, sewage disposal, water supply,
and ¿ re protection than the capitals of civilized Europe in 1800” (Christian,
Maps of Time, p. 321). The building of monuments such as the pyramids
could also provide employment and encourage innovation in areas such as
architecture, engineering, and mathematics.We have seen that there were several features of Agrarian civilizations that
tended to encourage innovation and growth. Yet we also know that in this
era, innovation was much slower than in the Modern era. Why? There must
have been other factors that retarded innovation and growth, and indeed there
were. We will describe some of them in the next lecture. ŶBentley and Ziegler, Traditions and Encounters, chap. 12.
Christian, Maps of Time, chap. 10.
Fernandez-Armesto, The World, chaps. 7, 8.Brown, Big History, chaps. 7, 8.
Chase-Dunn and Hall, Rise and Demise.
Mokyr, The Lever of Riches, Introduction, chap. 1.Essential ReadingSupplementary Reading