God’s existence can be rationally demonstrated

God’s existence can be rationally demonstrated
Five Proofs of the Existence of God by Edward Feser, Ignatius, 330pp, £16.50, reviewed by Christina Read.
Following on from his defence of Aquinas’s natural theology in The Last Superstition and Aquinas, Edward Feser has written a very useful book on five proofs of the existence of God. No, this is not specifically about Aquinas’ five ways but is Feser’s own treatment of his top five arguments for God’s existence in the history of western thought: the Aristotelian, the neo-platonic, the Augustinian, the Thomist and the rationalist. Rectifying their neglect by contemporary philosophy, he constructs a confident defence of classical theism.
Feser takes a very methodical approach to each proof, firstly setting out a two stage informal statement of the argument (“more discursive and leisurely”), then delineating a formal step-by-step analysis and finally addressing objections to the proof.
From potential to actual
So, in the case of the Aristotelian proof, which receives the lengthiest treatment, Stage 1 of the informal statement of the argument starts by considering the everyday experience of change and demonstrates logically from this the existence of a single first cause, Aristotle’s ‘Unmoved Mover’. Feser does this by considering the readily evident linear series of causes entailed in change (e.g. a cup of hot coffee is cooled by the surrounding air which was cooled by the air conditioning which was switched on by someone pressing a button etc.), introducing the notion of the actualization of potentials “as a way of making sense of change” (p.26) (Change can only occur if “things have potentials which can be actualized” p.24). From this he uncovers the need for a ‘changer’ or cause, something already actual that actualizes the potential (for “whatever goes from potential to actual has a cause” p.40).
Things can only change because they exist
Such linear causal series in which every member of the series has its own causal power are then shown to presuppose hierarchical causal series (the cup of coffee is held up by the desk, which is help up by the floor, which is held up by the foundations, which is held up by the earth) in which each member’s power to hold up coffee is derived from the earth upon which the whole series depends. Unlike linear series, hierarchical series of cause are therefore shown to trace down to a first cause from which all the other causes in the series derive their causal power. Change can therefore only be fully comprehended by tracing hierarchical series to their first causes. Change is presupposed by the fundamental question of existence (“things
can only change because they exist”, p.28), which, when considered in terms of hierarchical causal series must, like all such series, have a first member “which can actualize its potential for existence without having to be actualized itself” (28); “it just is actual” without any potential for existence requiring actualisation. This is pure actuality, (could not in principle have a cause), uncaused cause, Aristotle’s “Unmoved Mover” or, Feser thinks more precisely, “unactualized actualizer” (p.27)
It is only in Stage 2 of the informal statement that Feser explicitly states this as a proof for the existence of God, defending the identification of the Unmoved Mover with God as the ultimate cause of all things and arguing that the other qualities traditionally attributed to God follow on from what he has already set out in Stage 1. In the third section Feser’s take on the Aristotelian proof is expressed more formally as a 50 point summary, running from point 1 “change is a real feature of the world” to point 50 “God exists” via a point by point defence of the purely actual actualizer’s immutability, eternity, immateriality, incorporeality, perfection, goodness, intelligence and omnipotence.
Misunderstandings and objections
The final, lengthy section Some objections rebutted effectively addresses common misunderstandings without cluttering the initial argument or creating a profusion of lengthy footnotes. It also provides an opportunity for Feser to expound his view that subsequent philosophical and scientific models do not rebut the Aristotelian understanding of change and causation even if how the principle is applied is affected. Thus almost half the pages of his treatment of the Aristotelian proof are used to defend the reality of hierarchical causal series in the face of objections raised from Hume to Kant, Newton to Einstein, making close reference to developments in physics.
Making arguments accessible
Feser takes a similar approach with each of the proofs, the neo-platonic starting from the fact that things have parts, the Augustinian from the fact that there are abstract objects (e.g. universals, properties, numbers), the Thomist from the distinction in the things of our experience between what they are (essence) and that they are (existence) (i.e. the ‘real distinction’), and the rationalist from our experience of the fact that there are explanations for the things we encounter.
The approach helps make ‘God’ arguments accessible to an audience formed in an agnostic, materialistic/ atheistic worldview, whilst the methodology of starting with the informal statement and moving through the formal onto the refutation of objections to the proof opens the topic to the lay reader without neglecting a more formal philosophical treatment and the engagement in scholarly debate which pushes forward Feser’s contributions to academic reflection on this topic.
In all this he demonstrates striking explicatory skill, indicative of an effective teacher, starting his consideration of each proof with evident everyday experience such that the shift to specific consideration of God’s existence happens almost seamlessly. The frequent summaries of the argument add to the effectiveness of this approach, helping the reader keep track of the proof so far, whist also reiterating and reinforcing the main points.
What God is like
Feser’s detailed examination of all five proofs is followed by a further two chapters. The first develops something touched upon in his treatment of the five arguments - what the proofs for God’s existence might tell us about what God is like. The sixty-eight pages on ‘the nature of God and his relationship to the world’ sets out with high expectations of what natural theology can tell us not only of God’s existence, but also of his nature. The book then closes with a chapter tackling and dismissing further objections to what natural theology can tell us about the existence of God, such that Feser is confident that the once mainstream position in western thought (irrespective of religious/philosophical persuasion) “that God’s existence can be rationally demonstrated by purely philosophical arguments” (p.15) is shown to be irrefutable.
Philosophy, not theology
It is great to see the question of the existence of God re-emerging as worthy of serious academic treatment, and if you want a clear, up-to-date Neo-Scholastic statement of the arguments this may well be it. Feser’s defence of natural theology is exercised strictly in the arena of philosophy; there is no argument for its place in Theology per se, no gesture towards a statement of the relationship between reason and revelation, between natural and ‘revealed’ theology. What Jesus might have to do with any of this is completely off-terrain. In Feser’s approach here such matters begin where he leaves off: his stated concern is to get us to the place where such issues can be addressed. Of course what is also missing is the Hollowayan proof from unity … We look forward to its inclusion in the debate arising from this important return to the question of God’s existence.


Dr Christina Read studied for her doctorate in Theology at King's College, London. She is a member of the FAITH Movement and lives with her husband and children in London.

Faith Magazine

July/ August 2019