The concept of unintended consequences is one of the building blocks of economics. Adam Smith's "invisible hand," the most famous metaphor in social science, is an example of a positive unintended consequence. Most often, however, the law of unintended consequences illuminates the perverse unanticipated effects of legislation and regulation. In 1692 the English philosopher John Locke, a forerunner of modern economists, urged the defeat of a parliamentary bill designed to cut the maximum permissible rate of interest from 6 percent to 4 percent. Insurance is controlled by the courts, through appellate decisions, and by governmental agencies, through statute and regulation. Compliance with the appellate decisions, statutes, and regulations-different in the various states-is exceedingly difficult and expensiveThe business of insurance is, unfortunately, subject to the law of unintended consequences as if it were on steroids.