First Principles: What America's Founders Learned from the Greeks and Romans and How That Shaped Our Country

by Thomas E. Ricks

By having the self-confidence to apply the methods of scientific inquiry to human situations, they developed several new scholarly fields. In his magisterial study of the Enlightenment, Peter Gay states that Montesquieu invented sociology in The Spirit of Laws, that Edward Gibbon founded the modern writing of history with The History of the Decline and Fall of the Roman Empire, and that Adam Smith did the same for economics with The Wealth of Nations.57 (Xenophon’s Oeconomicus might from its title appear to claim to be a foundational document, but it really is about how to manage a household, which is what the word means in Greek.)58 Gay does not mention it, but Hume’s essay on “The Populousness of Ancient Nations” also was an early venture into creating the field of demography. Another Scot, James Hutton, came up with an astonishing new way to think about time, and so invented modern geology, a subject to which we will return. It is noteworthy that several of these innovative scholarly ventures—the ones by Montesquieu, Gibbon, and Hume—were rooted in the studies of the history of Rome.