The Theory of the Leisure Class (1899), by Thorstein Veblen, is a treatise on economics and a detailed, social critique of conspicuous consumption, as a function of social class and of consumerism, derived from the social stratification of people and the division of labour, which are social institutions of the feudal period (9th–15th c.) that have continued to the modern era.

Veblen asserts that the contemporary