About Karl Marx(5)

As historical materialism shows, the productive labor of the material means of life is the basis of the existence and development of human society. Labor and the means of production are always factors of production, and the combination of the two constitutes the productive forces. When people develop productive forces, they also develop certain interrelations, id est relations of production, which together constitute social relations. The nature of relations of production and social relations changes with the change of productive forces.