During his study of capitalism, Marx introduced the idea that the economic sphere dominates all other sociological institutions and systems. He defined the economic system as the social infrastructure of society, the base upon which all other social systems are constructed, dubbing the other social institutions as the social superstructure (Macionis, 1997: 77). Marx believed that these social superstructures were constructed upon the economic system, and therefore, extended the ideas of economics into other aspects of society. Marx saw this as a potential tool for usage by the capitalists, by which they were able to secure their wealth and holdings. An important aspect of Marx's description of capitalism is its irrationality. He believed it was an irrational system of production because it created large social problems by failing to meet the needs of so many, only beneficial to the small group of capitalists. Though irrational, Marx believed that capitalism was able to exist due to the sense of false consciousness which it conveys. Marx defines this false consciousness as the explanation of social problems as the fault of an individual's inadequacies, rather than sociological flaws existing in the capitalist society (Macionis, 1997: 78). This materialistic approach to the understanding of capitalism lead to Marx's ideas of class conflict as the motivational force driving sociological change throughout history. .
As quoted in Marx's Manifesto of the Communist Party, "The history of all hitherto existing society is the history of class struggles. Freeman and slave, patrician and plebeian, lord and serf.in a word, oppressor and oppressed, stood in constant opposition to one another." (Marx, 1978: 473). Using the idea of materialism, Marx traced class conflict through the different stages of history in order to explain the rise of modern industrial capitalism. Marx explained the concept of class in terms of economic factors, defining classes in relation to the means of production, or the technological and social means by which production is carried out in a society (Giddens, Sociology, 1993: 757).
