Henri Lefebvre (1901–1991) was a French sociologist, intellectual and philosopher who was generally considered a Neo-Marxist.
His Critique of Everyday Life, first published in 1947, was among the major intellectual motives behind the founding of COBRA and, eventually, of the Situationist International. Lefebvre dedicated a great deal of his philosophical writings to understanding the importance of (the production of) space in what he called the reproduction of social relations of production. This idea is the central argument in the book The Survival of Capitalism, written as a sort of prelude to La production de l'espace (1974) (The Production of Space). These works have deeply influenced current urban theory, mainly within human geography, as seen in the current work of authors such as David Harvey and Edward Soja. Lefebvre is widely recognized as a Marxist thinker who was responsible for widening considerably the scope of Marxist theory, embracing everyday life and the contemporary meanings and implications of the ever expanding reach of the urban in the western world throughout the 20th century. The generalization of industry, and its relation to cities (which is treated in La pensée marxiste et la ville), The Right to the City and The Urban Revolution were all themes of Lefebvre's writings in the late 1960s, which was concerned, amongst other aspects, with the deep transformation of "the city" into "the urban" which culminated in its omni-presence (the "complete urbanization of society").
In his book The Urban Question (translated into English very early, in contrast with Lefebvre's works), Manuel Castells heavily criticizes Lefebvre's theoretical arguments contained in the books published in the 1960s about the contemporary city from a Marxist standpoint. Castells' criticisms of Lefebvre's subjective approach to Marxism echoed the Structuralist school of Louis Althusser, of which Lefebvre was an early critic. Many responses to Castells are provided in The Survival of Capitalism, and some may argue that the acceptance of those critiques in the academic world would be a motive for Lefebvre's effort in writing the long and theoretically dense The Production of Space. In The Production of Space, Lefebvre contends that there are different levels of space, from very crude, natural space ('absolute space') to more complex spatialities whose significance is socially produced ('social space').