First Mover

First Mover: The origin of all motion in the Universe, an origin that is itself unmoved. The idea was introduced by Aristotle and developed by philosopher-theologians in all the three great traditions of Mosaic theism - Judaism, Christianity, and Islam. It provides the first, and he himself thought the most obvious, of the Five Ways of St. Thomas Aquinas. The premise is that there is, in a broad sense, motion in the Universe. So Aquinas urges, "everything which is in motion is moved by something else. But this cannot go on forever: because if it did there would be no First Mover, and consequently no other mover at all, since second movers do not move except when moved by a First Mover, just as a stick does not move anything except when moved by a hand. And so we must reach a First Mover which is not moved by anything: and this all men think of as God."