


Bandits may have sinister motives, but their actions follow a logic that allows others to predict and defend against them-they act out of a rational self-interest-while the stupid are “erratic and irrational.” The author gives all of this material a quasi-scientific air by calling his theories “laws” and by inserting graphs showing quadrants with X and Y axes, including four worksheets in an appendix that let readers fill in friends’ propensities for certain traits. The stupid gain nothing and may suffer losses as they harm others, and they are therefore the most dangerous. The helpless gain little from their actions, though others may profit the intelligent gain from their actions as others also benefit and the bandits gain as others lose.

The author takes a tongue-in-cheek, socio-economic view of human folly in a slim book that divides people into four groups-“the helpless, the intelligent, the bandit, and the stupid”-based on whether they and others gain or lose from their behavior. In a new edition of a self-published 1976 essay, Italian economic historian Cipolla (1922-2000) posits that the most dangerous people are the stupid ones.
