The short version of the point being made in this book seems fairly obvious. Anyone who has observed humanity very long (with the possible exception of psychologists, philosophers, and economists) would be aware of it. Humans are not rational animals. But calling them irrational is not quite correct, either, because sometimes, they can be, although not usually, and not often. If you want to know how humans answer questions, solve problems, make choices, or decide on courses of action, a rational decision-making model is not a good fit. This is because people have two distinct ways of thinking, fast and slow. The fast way, which the author calls System 1, is the one we usually use. It’s quick and based mostly on instinct and emotion. It’s the same basic thought process our ancestors used when facing a saber-toothed tiger a hundred thousand years ago. Then there’s System 2, which is slower, deliberative, and more difficult than System 1, but also does not guarantee a reasonable conclusion. It’s the system we (sometimes) use when approaching questions like 17 x 24. If we are patient and know enough math, we can answer the problem correctly. But when we aren’t or don’t, well, we might fall back on system 1, and respond with “blue” because we like that color.
The basic arguments of the book are illustrated by (far too) many psychological studies of the type where a group of (usually) students is given a hypothetical question to solve. Often, these relate to gambling, as in how much money would you bet for a chance to get even more? Here’s a non-gambling example (from page 186): Julie is currently a senior in a state university. She read fluently when she was four years old. What is her grade point average (GPA)? To me the answer seems obvious. It’s I don’t know. Ask her. But the book goes on for pages about how the test subjects answered this and what their thought processes most likely were. Well, okay, but is this really relevant to how humans act in the wild? Possibly, but I’d be cautious. Even when I was a Behavioral Science grad student (in the previous century), I was skeptical about these things.
Despite my curmudgeonly nit-picking, this is an interesting, if not overly surprising, book on human behavior. An unscrupulous politician or marketer might even be able to use it as a guide on manipulating people for fun and profit. (Actually, some probably already are.) It can get a tad repetitive, but for a scholarly tome, it’s quite readable.