At the end of October, I wrote a lot about Aristotle's proof for the existence of God. It turns out that I don't have to give a presentation about this topic, after all. Still, I want to try explaining the proof from motion again, this time in normal person language, not Ancient Greek Philosopher English.
Physics (and common sense) tells us that inanimate objects don't move themselves. If you see inanimate objects moving, the only correct logical deduction you can make is that someone moved them. For example, if I'm at the bowling alley and I see a moving bowling ball, I can deduce that someone rolled the ball. If I go to Egypt and see the pyramids, I can deduce that the stones were moved there.
This is all perfectly logical. I don't need to see the people who built the pyramids; I can deduce they existed, just from observing the pyramids. Likewise, if I see a series of dominoes, where one domino falls down and moves the next, I can logically and correctly conclude that the entire sequence of falling dominoes began with a first domino, which set the chain in motion.
(Obviously, physics and rules about motion are more complicated than that, but I'm purposely keeping things simple here.)
Aristotle applies the rule of "inanimate objects moved, therefore, a mover exists" to the universe at large. The universe has been constantly moving for the past thirteen billion plus years, and for the majority of that time, there were only inanimate objects. The logical deduction is that someone or something set the universe in motion, and this is what he called "God".
Aristotle wanted to prove the existence of the Greek gods, who keep things moving in the universe. Christians use a variation of the argument to prove the existence of a creator God, like the one found in the first book of the Bible, who set the universe in motion through the Big Bang.