Saint Thomas Aquinas was a Dominican monk who is widely considered to be the greatest Christian philosopher to have ever lived . Aquinas is mostly known for his Five Proofs, or Five Ways, regarding the existence of God. With the first of these Five Proofs, Aquinas observes that in this universe there exists change. In this context, change is described by the transition from actual to potentiality, and in order for there to be potential change, there must be actual change first. To cause change is just to draw something out of potentiality into actuality, and this can only be done by something that is in actuality. For example, something actually cold, like water, makes ice which is potentially cold become actually cold, thereby altering, or changing, that ice.…show more content… In turn, that other object is also being changed by yet another object that is also being changed itself, so on and so forth. Basically meaning, in this world, everything that changes is made to change by something else. It is therefore impossible for a thing that undergoes a change to cause that change, or for something to change itself. However, Aquinas believes that there must be something or someone that started the process of change from the beginning; something that was not being changed but instead created the development of change altogether. Aquinas calls this something the “unmoved mover”, who we have come to believe is God. Aquinas argues that God indeed must exist because change would then be nonexistent without a first changer. For instance, God would be considered the actual change, and every change that follows would be the potential. If God did not exist there would be no actual change, and therefore no potential