Unintended Consequences, Law of

It is a truism that human actions have unintended consequences. The sociologist Robert K. Merton, who authored a classic statement of the phenomenon in 1936, noted that the subject has been treated by virtually every substantial contributor to the long history of social thought. The “law of unintended consequences” quickly passed into public discourse. The concept continues to exert a fascination for social theorists, perhaps because it defines the province and basis for social scientific inquiry. Even though it is noncontroversial, its implications are not obvious, and this entry tries to elucidate some of them.