Aquinas’ Third Way to Prove God’s Existence

This is one of the Aquinas’ five ways for proving God’s existence. This is derived from the concepts of possibility and necessity. In his argument, he says that naturally, there are things that can be and those that cannot be because while they are generated, they are also corrupted. He goes ahead to argue that something that is not possible to be, cannot always exist. According to Aquinas therefore, if everything does not have the ability to exist, then at a particular time nothing existed.
If the above idea could have been true, then nothing would have been existing even now. This is due to the fact that one thing exists only through another that is already existing. According to this argument, Aquinas tries to explain that the non-existing things are created or originate from those that already exist. This is absurd. According to him, it is not possible for everything to have had the possibility of existing, but there is something whose existence is necessary. However, the necessity of everything is either caused by another or not. Hence it is not possible to go to infinity in an effort to explain the existence of necessary things that have been caused by another. As a result, Aquinas indicates that we have to admit that there is a being that existed not because its necessity was caused by another thing, but he is the one that caused necessity of others, and that is God.
We can therefore conclude that according to Aquinas’ third way of explaining God’s existance, God existed because of His own necessity and not that His necessity was caused by others. Moreover, God causes in other things their necessity. This is why we refer to Him as the creator of all that exists. This argument of Aquinas has been viewed as weak by other philosophers when on its own, but contains some strength when combined with the other four arguments of Aquinas.