Aristotle argued the universe needs one thing that causes motion without itself moving

Aristotle reasoned that every motion needs a cause, and that cause needs its own cause, which can't regress forever, so there must be a first, uncaused source of all motion in the universe. He called this the unmoved mover, a purely actual, unchanging being that moves everything else not by pushing it, but by being the object of its desire, an idea that later shaped medieval arguments for the existence of God.

— Aristotle, Metaphysics, Book XII (Lambda) — c. 350 BC
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