" Practical men, who believe themselves to be quite exempt from any intellectual influences, are usually the slaves of some defunct economist. ... in the field of economic and political philosophy there are not many who are influenced by new theories after they are twenty-five or thirty years of age, so that the ideas which civil servants and politicians and even agitators apply to current events are not likely to be the newest. "

― John Maynard Keynes , The General Theory of Employment, Interest, and Money