Lenin: Marx deepened and developed philosophical materialism to the full, and extended the cognition of nature to include the cognition of human society. His historical materialism was a great achievement in scientific thinking. The chaos and arbitrariness that had previously reigned in views on history and politics were replaced by a strikingly integral and harmonious scientific theory, which shows how, in consequence of the growth of productive forces, out of one system of social life another and higher system develops—how capitalism, for instance, grows out of feudalism. https://wordsmith.social/protestation/quotes#quote9601