The Alchemy of Finance [Paperback]

His philosophical tenet, Reflexivity, denotes a feedback loop: Individuals act on their views of a situation, thereby changing the situation. For example, if traders believe a stock is going up, they buy it, thereby bidding it up. But their belief caused the result; there may be no fundamental reason for the rise.
Thus what we think determines what we do and has consequences, but typically it is not correct.

Inspired by Heisenberg's rule about quantum particles, Soros proclaims a human uncertainty principle which suggests our understanding is often incoherent and always incomplete. From his case study, one notices that uncertainty continually besets Mr. Soros in managing his hedge fund, which has the same name as the particles subject to Heisenberg's uncertainty principle.

General models do not always translate into money making practice. But Soros provides an insight of great practical significance: traders need to be adaptive, because there is no way of knowing beforehand how a market situation will turn out.

The Quantum Fund experience demonstrates how that works. This exercise in global macro strategy, a master speculator's take on commodity, currency and equity markets, is a a litany of doubts and hazards.

He's been losing on currency trades for several years. Then in September 1985, he makes a killing by buying a lot of yen just before central banks switch to a new exchange rate system and the yen rises. There is a pattern: he sustains losses, reduces positions, gets out, then sees a great opportunity and pounces. In short, he constantly and quickly adapts to events.

Despite various setbacks, Quantum Fund's NAV per share rose 121% in 1985 and 43% in 1986. Such numbers make for legend and Mr. Soros became one.

How did he do it? He keeps an open mind and continually modifies his outlook with new information. As he remarks, "the markets provide a merciless reality check," and Mr. Soros never stays with an idea that fails the test. Most of the time he can't predict what's coming, but he promptly corrects course in response to feedback. That limits losses. On rare occasions he can see through the fog of uncertainty and hauls in the booty.

This is not an easy book to read, but as another hedge fund manager, Paul Tudor Jones, describes it in the foreword, it is a timeless guide.

Here's an example:
"[the shoelace theory]...can be interpreted as a synthesis of Hegel's dialectic of ideas and Marx's dialectical materialism. Instead of either thoughts or material conditions evolving in a dialectic fashion on their own, it is the interplay between the two that produces a dialectic process."

This passage is a microcosm of the entire book: he makes a valid point, but it's not a particularly significant or difficult point. The only difficulty is in parsing his turgid language. I sense he is a great investor who wants to be considered a great thinker, and he believes that in order to accomplish this he has to use big words to express his theories.

Soros's widely praised theory of reflexivity is a valuable contribution, but he doesn't need 400 pages to convey it. I didn't read this book expecting a "how to make money in the stock market" tutorial, but I did expect to gain a better insight into how the markets function. I did not get that.

Don't waste your time.