Keynes versus the Classics: Round Two

LONDON – The economist John Maynard Keynes wrote The General Theory of Employment, Interest, and Money (1936) to “bring to an issue the deep divergences of opinion between fellow economists which have for the time being almost destroyed the practical influence of economic theory…” Seventy years later, heavyweight economists are still at each other’s throats, in terms almost unchanged from the 1930’s.

The latest slugfest features New Keynesian champion Paul Krugman of Princeton University and New Classical champion John Cochrane of the University of Chicago. Krugman recently published a newspaper article entitled “How Did Economists Get It So Wrong?” There was nothing in mainstream economics, Krugman wrote, “suggesting the possibility of the kind of collapse that happened last year.”

The reason was that “economists, as a group, mistook beauty, clad in impressive-looking math, for truth.” They purveyed an “idealized vision of an economy in which rational individuals interact in perfect markets.” Unfortunately “this sanitized vision of the economy led most economists to ignore all the things that could go wrong.” So now economists will have to accept “the importance of irrational and often unpredictable behavior, face up to the often idiosyncratic imperfections of markets and accept that an elegant economic ‘theory of everything’ is a long way off.”

Krugman’s heavy pounding of Chicago School economics goaded Cochrane, a professor of finance, into some bad-tempered counter-punching on the university’s Web site, much of which consisted of a personal attack on Krugman’s scientific integrity. When he gets around to economics, Cochrane aims his blows at two points: Krugman’s attack on the “efficient market theory” and his advocacy of “fiscal stimulus” for depressed economies.