The Myth of the Rational Market by Justin Fox ****

The Myth of the Rational Market by Justin Fox is just what it claims to be: a history. However, since this is the (checkered) history of an idea that has never been fully accepted or rejected, don't expect any narrative arc, climax or resolution.

The concept of a rational market at various times has meant that markets are correct, will soon be correct, or might be correct eventually. It might also imply that no one can beat the market, or those that beat the market were just lucky, or to beat the market consistently is very hard. Regardless of the interpretation, academics and practitioners have used this investigation to earn Nobel prizes and/or billions of dollars. Sometimes the focus is on the future (usually during boom times) and at others on the past (usually after crashes).

Justin Fox is an exhaustive researcher and covers the ground in detail with adequate mention of every significant economist, policy wonk, financial analyst, and money manager of the 20th century. Harvard, MIT and Chicago get the most mentions but many other schools are also mentioned.

If you are interested in the history of economic and finance, you will not be disappointed.

If you are interested in investing advice, here it is: Buy and hold index funds. This has been the answer since Vanguard introduce such funds in 1976.

If you want to know if it is possible to do better, the answer is a resounding yes; markets are inefficient and a few very smart folk with enormous resources beat them from time to time.

If you want to know whether you can do better, forget it!

Those are the short answers. The long form also makes interesting reading.