A while ago, Laurence Gonzales's "Deep Survival" was reviewed here. That was a great book, but left one big unanswered question.

One of Gonzales's conclusions was that many wilderness disasters were caused by experienced, knowledgable people doing abysmally stupid things (ski rescuers choosing to go snowmobiling on posted avalanche slopes, river rafting guides going out in raging torrents etc. Feel free to add "Into Thin Air" Everest guides to the data set). As an experienced knowledgable person (IMO, LOL) I really want to know what would lead these supposedly smart people to do this incredibly dumb stuff.

Kahneman's book is about cognitive psychology. His thesis is that there are two ways in which people make decisions.

"System 1" is immediate reaction, a brain's method of creating an instantaneous coherent world view and generating a reflex reaction on that basis. You're a caveman, hear a rustle in the grass to your right, and point your spear in that direction literally* before you have a chance to think. You're on your snowmobile and see this big patch of virgin snow and you think "Awesome ...". System 1 evolved in humans because thinking fast is sometimes more important than thinking smart. This is still good some of the time (slight tug on a fishing line?), but System 1 can make very bad decisions on other occasions.

"System 2" is conscious thinking: doing math problems, writing a coherent paragraph, weighing political arguments and credibility when reading an article in the newspaper, looking at a stretch of whitewater from shore and deciding "Am I skilled enough to do this". System 2 takes work. System 2 can get overloaded easily, and even in no-brain situations, some people are just plain lazy about thinking. System 2 (the body's whole nervous system actually) requires lots of glucose, so it's hard to make System 2 (rational) decisions when you're glucose-depleted, and you fall back on System 1.

I'm not going to spoil the whole book for you. There's lots more on why System 1 is sometimes so dumb, and why people make so many decisions using System 1 instead of System 2 even when no instant decision is required.

I originally stumbled upon this book because it made a lot of reviewers' lists of best books of 2011, and because Kahneman got the Nobel prize in economics** in 2002 for his work on why stock market investors make dumb decisions. (Other investors, not me. I always use 100% System 2 in stock-picking, that's why it took me 10 years to get around to reading Kahneman first-hand.)

Daniel Kahneman is a very good writer, so you don't need a psych background to follow his reasoning. Strongly recommended for anyone who takes the time to think about anything.


*yes literally. There's lots of background supporting this.
** I know economics isn't a "real" Nobel prize, but let's not argue about picky stuff like this.