Keynes Is Popular Again

I pointed to this trend in a previous post: the work of John Maynard Keynes has been largely disregarded for the past 50 years as out-dated. Recently, however, people are starting to take his work seriously again. Here is another excellent column on why Keynes seems valuable again. The key point (behavioral economics strikes again!) is quoted here, and as usual, emphasis in bold is mine:

The General Theory is a hard slog, though not because it is mathematical. There is some math, but it is simple and, with the exception of the formula for the "multiplier" (of which more shortly), it is incidental to Keynes's arguments. A work of elegant prose, the book sparkles with aphorisms ("It is better that a man should tyrannize over his bank balance than over his fellow-citizens") and rhetorical flights (most famously that "madmen in authority, who hear voices in the air, are distilling their frenzy from some academic scribbler of a few years back"). But it also bristles with unfamiliar terms, such as "unit-good" (an hour's employment of ordinary labor), and references to unfamiliar economic institutions, such as a "sinking fund" (a fund in which money is accumulated to pay off a debt). ...

It is an especially difficult read for present-day academic economists, because it is based on a conception of economics remote from theirs. This is what made the book seem "outdated" to Mankiw--and has made it, indeed, a largely unread classic. (Another very distinguished macroeconomist, Robert Lucas, writing a few years after Mankiw, dismissed The General Theory as "an ideological event.") The dominant conception of economics today, and one that has guided my own academic work in the economics of law, is that economics is the study of rational choice. People are assumed to make rational decisions across the entire range of human choice, including but not limited to market transactions, by employing a form (usually truncated and informal) of cost-benefit analysis. The older view was that economics is the study of the economy, employing whatever assumptions seem realistic and whatever analytical methods come to hand. Keynes wanted to be realistic about decision-making rather than explore how far an economist could get by assuming that people really do base decisions on some approximation to cost-benefit analysis.

The General Theory is full of interesting psychological observations--the word "psychological" is ubiquitous--as when Keynes notes that "during a boom the popular estimation of [risk] is apt to become unusually and imprudently low," while during a bust the "animal spirits" of entrepreneurs droop. He uses such insights without trying to fit them into a model of rational decision-making.