This article presents an intellectual and social history of the concept of the baby boom. Researchers first invented the notion of a population bulge in the mid-twentieth-century United States to explain birth rates that were higher than predicted by their theories of a mature population and economy. As the children born during this “baby boom” entered schools in the 1950s, they were drawn into a pre-existing conversation about an educational emergency that confirmed researchers’ suspicions that the bulge would spread crisis over time throughout all of the nation's age-graded institutions. New sociological and demographic explanations of the bulge subsequently merged with heightened talk of generational conflict during the 1960s and 1970s to define, with journalistic help in 1980, the “baby boom generation” and the “baby boomer.” Crisis talk has pursued the boomers into the present, mobilized most effectively by opponents of the welfare state.

The Science of Difference examines life insurance companies' significant impact on the development of systems of human classification and discrimination in modern America. It pays closest attention to the tools employed by life insurance companies to enable and justify their discriminatory practices, tracing their evolution over the course of the nineteenth and early twentieth centuries. Companies used life tables to think about sectional difference prior to the civil war; they collected statistics to defend the propriety of racial discrimination; and they revolutionized risk by inventing the medical “impairment.” Drawing on company archives and personal papers, as well as a wide range of publications, the dissertation describes corporate research in the financial industry, argues for the importance of cultural factors in tracing business history, and shows how the industry built a national statistical community with tools designed to measure and price human difference.