The Unmoved Mover
"God is the first mover, Himself unmoved."
— Thomas Aquinas
Imagine sitting quietly in a park and watching a child roll a ball down a hill. You know instinctively that the ball didn’t begin to move by itself — someone had to give it that first gentle push. It’s such a simple image, yet it holds one of the oldest and most profound questions humans have ever asked: What set everything in motion?
Thomas Aquinas, writing in the thirteenth century, used that kind of everyday observation to reach toward something vast. He wasn’t just speaking of physical motion — of stones rolling or planets spinning — but of change itself: a spark igniting wood into flame, a seed swelling and splitting to become a tree, a thought awakening in the stillness of the mind. All movement, all change, Aquinas said, begins because something else acted first.
But follow that chain backwards — like tracing a row of falling dominoes to the one that was first tipped — and you arrive at a question that echoes through every age: What was the first cause? If every motion is the result of a prior motion, then at the root of everything must be something that moves without being moved, changes without being changed, causes without being caused.
For Aquinas, that source is God — the First Mover, eternal and unchanging, the reason there is something rather than nothing. Without such a source, he argued, the entire sequence of causes and effects that make up the fabric of reality would have no foundation. It would be like a line of dominoes falling with no first push — an impossibility.
Some will object and say, “The chain has always existed. There is no beginning.” Others will point to the Big Bang and the vast explanations of science. Yet even there, Aquinas’ question lingers stubbornly: Why is there anything at all, rather than nothing? Science may trace the unfolding of the universe back to an initial singularity, but it cannot explain why that singularity — or the laws that shaped it — existed in the first place.
Aquinas invites us to look beyond the physical chain of events to the ground of being itself — to the One who is actus purus, pure actuality, the source of all potential. God does not simply start the universe like a watchmaker winding a spring. God is the reason motion, existence, and being are possible at all. The universe is not an accident; it is a masterpiece, and behind every brushstroke is the hand of the Artist.
It’s worth pausing to feel the weight of that thought. When you next watch a leaf drifting down a street in autumn or see the tides rising and falling beneath a silver moon, consider that none of this happens in isolation. Every motion is part of a vast, unfolding story that began — and is sustained — by One who was never moved Himself.
The ancient poet of Job heard the same question whispered in the night sky:
Can you bind the chains of the Pleiades
or loosen the belt of Orion?
Can you bring forth the constellations in their seasons
or lead out the Bear and her cubs?
Do you know the laws of the heavens?
Can you set their dominion over the earth?
— Job 38
Behind every falling domino, every rolling ball, every star in its appointed course, is the same mystery Aquinas tried to name: the Unmoved Mover. And the truest wisdom is not to solve that mystery, but to revere it — and let that awe change how we live.
Image by Copilot