Explain how “worrying about mere possibilities while ignoring probabilities” can result in people making decisions that not only fail to satisfy social interest, but also fail to satisfy self-interest.
We pride ourselves on being the only species that understands the concept of risk, yet we have a confounding habit of worrying about mere possibilities while ignoring probabilities, building barricades against perceived dangers while leaving ourselves exposed to real ones: 20% of all adults still smoke; nearly 20% of drivers and more than 30% of backseat passengers don’t use seat belts; two thirds of us are overweight or obese. We dash across the street against the light and build our homes in hurricane-prone areas—and when they’re demolished by a storm, we rebuild in the same spot.