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Proof for the Existence of God
The first of Aquinas’ five ways
Metaphysical questions tend to consider the nature of the world and reality, and why it is this way. Often in explanation and answer to cosmological questions, God is the resulting answer. Questions concerning the how and why of the world often becomes categorised in terms of causes and God often seems the best, and most understandable explanation of causes. Thomas Aquinas is one philosopher who attempts to argue for God’s obvious existence given features of the world which requires God for an explanation. He offers five arguments in support of God, the first of these concerning change. The validity of these arguments though are not wholly reliable as God’s existence is not universally believed.
Traditionally, one specific things existence can be explained in terms of its cause(s). But why do these causes exist? Further, how can the whole series of causes be explained in terms of the existence of the world as a whole? Commonly this question would be answered with reference to God, God being sufficient reason for its own existence, the uncaused cause. The a posteriori arguments in favour of God, as originally put forward by Aristotle, follow a general pattern:
Base Evidence: There is some fact, x, of empirical reality, which needs explanation.
Regress Exclusion: Explaining each empirical fact, x, by suggesting further empirical fact or cause, y, produces a vicious regress making x itself unexplainable
Meta-Empirical Inference: Therefore, the explanation requires a metaphysical being to account for the starting fact x: this is God
Aristotle’s point of view stems from his notion of change. Change for Aristotle is merely actualisation of potentia in which it is possible for something to change only if this change was already a potential state for the thing in change. In order for change to occur there must be a cause, y, for the change which is already what x is only potentially, this cause y must therefore be distinct from x. Applying the regress exclusion to this would make it impossible to explain x’s very changing. That is, unless there is a first origin of movement which is itself immaterial and pure actuality as it cannot be in change and becoming itself. This is the unmovable mover according to Aristotle. In order to explain how this unmoved mover is able to interact with material beings without being in change or having a material body itself, Aristotle claims it is not the efficient cause but rather the final cause. In being the final cause, the unmoved mover is the goal of all change, the end at which everything aims as this final cause is the most perfect being. Aristotle also argues that this unmoved mover, this most perfect of being, comprises mostly of thought as this is taken, by Aristotle, to be the most perfect activity. So, in order for this unmoved mover to be the most perfect object, it must be thoughts of the most perfect being, thinking of itself.
Aquinas proposes five ways to prove Gods existence, all of which follow the structure of a posteriori arguments: Base Evidence, Regress Exclusion, Meta-Empirical Inference. Aquinas begins from the position that it seems there is no God due to evils existing, and the cause of thing’s happening in this world can be observed within this world without assuming a God. The first way Aquinas proposes for the existence of God is the prima manifestior via. The base evidence this argument is change, much as Aristotle‘s argument. Although ‘anything changing is being changed by something else’ (Aquinas cited Crane, Farkas 2011: 31). This can be seen in all observable examples of changes. For example, the heat of fire cause the wood, which had previously only the potential to be hot, to actually become hot. When hot, this wood can only have the potential to be cold, as it cannot be hot in actuality and potentially. Therefore, change cannot be caused by the object in change but must be changed by something else. These causes of change though must have also be the result of a pervious change upon it, and so the list continues, apparently into infinity, regress exclusion. This though cannot go on into infinity as this would mean there would be no first cause to begin the changes, and so no subsequent changes, the Meta-Empirical Inference. So, it would seem there must have been a first cause of change which doe not itself change, this must be God.
In argument to Aquinas’ first account for God, the general structure of his argument can be contested. In Base Evidence, the assumption that change and the general existence of an external material world could be denied by sceptics. However, more generally the question is raised as to why the existence of change requires an explanation. This can be seen in the ‘Brute Fact’ view which claims that ‘reality merely happens to be as it is’ (Derek Parfit cited in Crane, Farkas 2011: 24). In disagreement with the regress exclusion, it could be questioned whether causes leading into infinity were actually an impossibility. It would seem that this idea does not include any contradiction so why should it not be so? Further, in terms of Aquinas’ claims to have provided evidence for God’s existence, it is asked what this first cause has in common with the Christian idea. Aquinas was seeking to claim the existence of a God in terms of the traditional Christian conception. This would mean God in the sense of being omnipotent, omniscient and benevolent. The concept and existence of evil though contends this, why would a benevolent God allow for evil? Augustine attempts to explain this as God only allowing necessary evil, God ‘would not allow any evil at all in his works if he wasn’t sufficiently almighty and good to bring good even from evil’ (Crane, Farkas 2011: 33). Despite this it could more easily be the case that this first cause merely exists to have caused the world, not to impart good or design onto it. Thus, Aquinas’ assumption that this first cause is God seems a further step from the evidence of ‘something whose nature we do not yet know’ (Crane, Farkas 2011: 6). Could it not be that the first cause is the universe itself, why must the explanation extend to a God? If there must be a first cause, an uncaused cause, why must this be external to the universe, could it not be the universe itself which began the chain of causes?
In conclusion, Aquinas’ attempt to explain God in terms of cause does seem by many to be relatively convincing as an explanation. Those who support the philosophical notion of a God continue to use Aquinas’ arguments for support. However, these arguments are often easily refuted. Although the notion of God is not necessarily a more obscure or unbelievable explanation for the existing chain of causes than others, it does not rise above these other ideas. Any claim that this philosophically supported God fulfils the notions of God set out by Christianity seem to entirely lack any evidence, instead it seems to be a massive leap from the given argument from cause. Further, the universe may not need an explanation, many argue under the brute fact view that the world is just coincidentally as it is. Causes needing a first cause is not necessary, it could be that the chain of causes stretches into infinity, there is no evidence to suggest this it to impossible. So it seems, if one is looking for evidence in support of God, Aquinas’ five ways is a place to start, yet they are fairly simply refuted.
Crane, T. Farkas, K. 2011 . Metaphysics: a Guide and Anthology. Oxford University Press.