Marx's theory of historical materialism is historical . It is historical because marx has traced the evolution of human societies in terms of their material or economic bases . Materialism simply means that it is matter or material reality which is the basis for any change. According to Friedrich Engels the theory of historical materialism was discovered but Karl marx , but marx thought it was Engels who has conceived the materialist formulation of history independently. We shall say that both of them used this theory to quote Marx as the "guiding thread " of all their works