The marketing professor Vladas Griskevicius thinks we humans are not nearly as stupid as he once thought.
Yes, we can drop $3,200 on engagement rings when many marriages end in divorce or spend $5,000 to $7,000 more on a Toyota Prius hybrid than a fuel-efficient conventional car, but he said that we have perfectly rational reasons for doing so.
Not that we really understand why these choices were rational, because we probably didn't get that our brains were trying to achieve some deep-seated evolutionary goal.
Griskevicius teaches at the University of Minnesota's Carlson School of Management and was trained as a psychologist, and his writing partner in a new book coming out next week, Doug Kenrick, is a psychology professor at Arizona State. Their term "deep rationality" is the key idea in their entertaining and informative book called "The Rational Animal: How Evolution Made Us Smarter Than We Think."
The idea that we humans are not that smart comes from behavioral economics, which seeks to apply principles from psychology to deepen the understanding of how people make economic choices. The neoclassical economists think people carefully and rationally choose options to maximize their well-being, and the behavioral economists say that people aren't really capable of doing that.
Flip a coin and get tails five times in a row, for example, and everyone knows the odds strongly favor getting heads the next time.
Wrong. That's called the gambler's fallacy.
Then there's the clustering illusion, the tendency to see patterns where none exist, and the hindsight bias that causes people to react to new information by saying they knew it all along. Many other biases have been identified, and one particularly strong one is that we secretly think it's everyone else who is the complete fool.