"Weltgeist", the world spirit concept, designates an idealistic principle of world explanation, which can be found from the beginnings of philosophy up to more recent time. The concept of world spirit was already accepted by the idealistic schools of ancient Indian philosophy, whereby one explained objective reality as its product. (See metaphysical objectivism) In the early philosophy of Greek antiquity, Socrates, Plato and Aristotle all paid homage, amongst other things, to the concept of world spirit. Hegel later based his philosophy of history on it.