This paper will examine the first of five cosmological arguments of St. Thomas Aquinasâ€™ â€œFive Waysâ€, which Aquinas claims to be the more obvious way to prove the existence of God (Hankim 199). Aquinas begins with the premise that there are things that exist in the universe. He then proceeds to the existence of motion as an example of things that exists in the world. Or as John H. Hick says,
Aquinasâ€™s proofs start from some general feature of the world around us and argue that there could not be a world with this particular characteristic unless there was also the ultimate reality which we call God. (20)
Aquinas uses the existence of motion to demonstrate the existence of God. He argues that since everything in the world is in motion -- for instant, the earth in constant movement -- therefore, whatever is in motion must have been set into motion by something else, or in Aquinasâ€™ words, â€œWhatever is moved is moved by anotherâ€ (Hankim 199). This is to claim that nothing that moves is itself self-generated. Aquinas argues that whatever is in motion, before it moves, has the potential to move; for example, a ball has the potential to be in motion and once it is in motion that potential for motion has been actualized. Once the ball starts moving, it no longer has the potential to move because it is now actually moving, or as in Aquinasâ€™ words the ball has gone from â€œpotentiality to actualityâ€.
Nothing can be potential and actual simultaneously. In this case, the ball cannot be both the mover and moved; that is, it can only be in one state at a time. Secondly, suppose that I have set a ball in motion to hit another object and that other object in motion, it is not to claim that the ball that I moved is the mover that actualizes the potentiality in the subsequent object. Rather, I, the ball, the subsequent objects and events are intermediate events in a series