Karl Marx's theory of alienation describes the social alienation, Entfremdung (estrangement), of people from aspects of their human nature as a consequence of living in a society made up of social classes. The alienation from the self is a consequence of being a mechanistic part of a social class, which estranges a person from their humanity, dehumanising them. Simply meaning; people become dissociated from their own humanity as people become cogs in the machine that is capitalism. 

It is popularly believed that communism makes everyone the same where in reality it is capitalism that does this. Capitalism, through monopolistic competition, discourages invention and does not allow the population to have a unique experience. The theoretical basis of alienation within the capitalist mode of production is that the worker loses their ability to make unbiased decisions as they are deprived of the right to think for themselves as the director of their own actions. Although the worker is an autonomous, self-realized human being, as an economic entity this worker is ,subconsciously or consciously, directed to goals and to activities that are dictated by the bourgeoisie in order to obtain from the worker the maximum amount possible.