Pierre Guillaume Frederic le Play

Pierre Guillaume Frédéric le Play, also known as Frédéric Le Play, was a French engineer and sociologist who developed techniques for systematic research on the family. He was interested in social questions since his youth and befriended a follower of the socialist thinker Saint-Simon. He travelled extensively around Europe as a mining expert and collected data on the budgets and living conditions of working-class families. He published his findings in a six-volume study called Les Ouvriers Européens (The European Workers) in 1855, which won the Montyon prize from the Académie des Sciences. He also founded the Société internationale des études pratiques d'économie sociale (International Society for Practical Studies of Social Economy) in 1856 and the journal La Réforme Sociale in 1881. He was appointed as a senator in 1867 and entrusted with the organization of the Exhibition of 1855 by Emperor Napoleon III, who admired his work. He died in Paris in 1882. Le Play opposed the idea of society's continuous evolutionary progress and advocated for social stability and moral authority based on the family. He proposed a theory of cyclic changes in society that were related to rises or declines in family morale. He also developed what is now known as the case-study method, in which a field-worker lives with a family for a period of time and gathers data on their income, expenditures, attitudes, and interactions. He classified families into three types: stable, unstable, and anarchic, based on their degree of solidarity and tradition. He favored the stable type, which he observed among peasant families in rural areas, and recommended its extension to the whole society. He also supported educational reform, industrial cooperation, and social welfare. Le Play's influence was significant in France and abroad. He inspired several social movements, such as the Catholic social movement led by René de La Tour du Pin and Albert de Mun, the regionalist movement led by Frédéric Amouretti [ fr] and Edmond Demolins, and the solidarist movement led by Léon Bourgeois. His followers formed the École de la Paix Sociale (School of Social Peace) and continued his work after his death. His case-study method influenced the development of statistical sampling and social survey methodology. His ideas also had an impact on sociology, anthropology, geography, history, economics, and political science.