French Sociolog, Philosopher, Historian Henri Lefebvre's "The Sociology of Marx" is one of the best sociological work about Karl Marx's social philosophy - Karl Marx's view on the political economics of modern capitalist societies. In the world, there are a lot of Marxist sociologs or a lot of sociology researchers who work about Marxism. But, Henri Lefebvre's "The Sociology of Marx" concentrates on Karl Marx's writings, books which are related to sociology as a social science. So, Henri Lefebvre writes on the different sociological concepts, categories and paradigms when he is thinking about the sociology of Karl Marx. For Henri Lefebvre, one of the key concepts of Marx's sociology is the necessity - Henri Lefebvre writes the human being is the exist of necessity, during the history, the human beings, individiually, or as a society, need somethings, the necessity of anything is the main or the central thing to be exist in the world (Henri Lefebvre in his "The Sociology of Marx" writes the principles or the concrete views of Karl Marx on the different social relations, social conflicts-changes, social productions-consumptions, social structures, and social historical experiences.)