Category Archives: Aquinas

Tidying Up 2: Aquinas’ Five Ways

And here is another directory: to my posts on Aquinas’ Five Ways.

2 Mar 2008, Reading the Five Ways 1. Putting the Ways in Context
2 Mar 2008, Reading the Five Ways 2. Who is Aquinas Trying to Convince?
3 Mar 2008, Reading the Five Ways 3. The Emptiness of the Ways
4 Mar 2008, Reading the Five Ways 4. The Intelligibility of the World
4 Mar 2008, Reading the Five Ways 5. Using Aristotle
4 Mar 2008, Reading the Five Ways 6. The First Way
4 Mar 2008, Reading the Five Ways 7. The Second Way
5 Mar 2008, Reading the Five Ways 8. The Third Way
5 Mar 2008, Reading the Five Ways 9. The Fourth Way
6 Mar 2008, Reading the Five Ways 10. The Fifth Way
6 Mar 2008, Reading the Five Ways 11. ‘This is What Everybody Understands By God’?
9 Mar 2008, Reading the Five Ways 12. The Ways to Mystery
13 Mar 2008, Reading the Five Ways 13. The Five Ways as Foundation
13 Mar 2008, Reading the Five Ways 14. Absolute Dependence
13 Mar 2008, Reading the Five Ways 15. On Not Following Aquinas
29 Jul 2008, Reading the Five Ways 16

Reading the Five Ways 16

In my earlier explorations of Aquinas’ Five Ways (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15), I made the following suggestion for what the argument would look like if addressed to an atheist (having earlier argued that atheists were not the primary addressees).

If, then, we are to translate Aquinas’ argument into a form suitable for an atheist audience, we might delete his claim that ‘everybody’ will happily use ‘God’ to name the end-point to which the Five Ways point. We might, instead, simply say: ‘Let X be whatever it is that answers these questions without begging further questions. X is the unmoved mover, the uncaused cause, the self-existent cause of existence and so on. Now, what manner of reality must this X be?’ … All this means, to repeat the point once more, that the Five Ways are radically incomplete on their own. Only if you carry on into the much longer and much more detailed arguments in Questions 3 to 11 of the Summa – the doctrine of divine Simplicity, and what follows from it – do you find Aquinas discussing the kind of reality that his proofs have demonstrated. And so only if you carry on into that material can you judge whether Aquinas is right to call it ‘God’.

I’m not quite so convinced of that point now – or rather, I think I put it a little too strongly. It seems to downplay at least the fourth and fifth ways, which lead Aquinas to more positive characterisations of this ‘X’, because they lead him in some sense to attribute, respectively goodness (or, better, perfection) and intelligence to this X that undergirds the world. Nevertheless, that weasel phrase ‘in some sense’ remains a necessary part of that sentence – and I think it means that I can still more-or-less keep hold of my point: Aquinas has yet to discuss what on earth we might mean by attributing such things to the uncaused cause, the unmoved mover, of the other ways, and is yet to connect that to the fuller language of Christian theology, with its descriptions of God in personal terms. Nevertheless, the ‘X’ is not as bare as my earlier comments might have suggested, and the leap to calling it ‘God’ not quite as foolhardy.

Note that this is simply a claim about what Aquinas was up to with the Five Ways, not a claim about whether they work. I’m still of the opinion that they can only really be retrieved as a proposal for a metaphysical articulation of Christian claims about creation: a way of naming the world’s contingency and of reading that contingency as God’s gift, and of reading the mystery of God’s life as deeper than such contingency. But precisely because I am interested in that kind of retrieval, I think the Fourth and Fifth ways – particularly the Fourth – much more interesting and suggestive than their evident weakness as arguments addressed to contemporary atheists might suggest.

Dawkins on Aquinas, again

Ch. 3: Arguments for God’s Existence

Aquinas and DawkinsJust in case you can’t be bothered to work through my posts on the Five Ways (I won’t hold it against you), here’s a quick summary of what I think is wrong with Dawkins’ presentation of Aquinas’ proofs for the existence of God. It is not, by the way, that I think Dawkins gets to the wrong basic conclusion: I too think that the Ways don’t quite work as a proof of the existence of God. But I find Dawkins’ mistakes in presentation interesting.

First, the minor points. I would have liked Dawkins to have the grace to acknowledge that the mysterious Fourth Way might have made more sense in Aquinas’ intellectual context than it does in ours – and to have done the minimal research required to know that the examples he (Dawkins) gives are not the kinds of gradation Aquinas was talking about. Once again, Dawkins is all too eager to represent a religious thinker as incoherent buffoon. I would also have liked him, purely for the sake of conceptual hygiene, to note that the Fifth Way is not quite the standard design argument (it’s not about things ‘looking designed’, but about apparently purposive action) – even though it is, I think, very nearly as vulnerable to Darwin.

The major point, though, is that Dawkins simply misses one major strand of Aquinas’ argument. Dawkins’ main complaint is that Aquinas arbitrarily invokes God as the end of the regress that the first three ways point to. Whereas, in fact, Aquinas argues at great length about what would count as an end to those regresses – and Dawkins doesn’t even hint that he’s aware of that part of Aquinas’ account. Far from simply asserting, Aquinas argues, in detail and at length – and Dawkins has missed that completely. (As for his aside about omniscience and omnipotence: well, if he had read on in Aquinas’ account, he’d know that whatever the silly little argument he offers is about, it isn’t about the God discussed by Aquinas.)

Aquinas, by the way, would clearly have thought Dawkins’ own answer – that we can terminate the regress with the big bang singularity or some other natural phenomenon – quite as vacuous as Dawkins’ thinks his, and that the supposed analogy with the natural termination to the divisibility of matter was wholly beside the point. To say that we can’t, in fact, go on dividing matter for ever is not quite the same as saying that at some point we can’t go on asking Why? Dawkins, in Aquinas eyes, is giving up on the intelligibility of the universe.

Note two things. First, I think this is a place where Dawkins fails to see the necessity for philosophy. That is, he thinks that the regress is going to be answered by a scientific discovery, by some physical concept – whereas I’m with Aquinas in thinking that once we get to questions like, ‘Why is there something rather than nothing’, we are inevitably beyond physics, and in the realm of metaphysics.

The second, I think that Dawkins regards Aquinas’ argument as an obvious failure because, unlike Aquinas, he is operating with a picture of God as one particular kind of thing – one of the things that there is – which is therefore clearly just as contingent, just as question-begging as any other particular thing. Aquinas and Dawkins don’t just disagree about whether God exists; they disagree about what ‘God’ means.

Reading the Five Ways 15

Reading the Five Ways
15. On not following Aquinas

With this fifteenth post, I come to the end of my little exploration of the Five Ways. [Edit: not quite.] I’m not sure why I embarked on it, to be honest. I think I simply wanted to see what I really made of a famous theological text that in the past I have tended to dismiss.

Well, it turns out that I’m still not convinced by the Five Ways when they’re playing the role most often assigned to them – i.e., when they are held to be ‘proving the existence of God’ in the most straightforward sense of that phrase.

I hope I’ve made it clear that I have various problems with the details of the Ways. The fifth leaks like a Whitehall department; the fourth relies (in its present form) on presuppositions not now widely shared; the first needs work to translate it from medieval to modern physics (even though it is not simply a physical argument); and the third as it stands is formulated very strangely. Nevertheless, I hope I’ve also made it clear what form I think the basic argument behind the Ways takes, and that I think it can at least be put forward plausibly

However, I do not think that the job will be done even by a more detailed reconstruction of the Ways around the more basic argument that I have sketched. On the one hand, I am not absolutely convinced that the metaphysical grammar assumed by the Ways is unavoidable. There may, for instance, be other ways of formulating the question that make different kinds of answer work, or that make it less clear that Aquinas’ answer does the job required of it, or that make the question itself less compelling. That I can’t see such alternatives is unsurprising: I am no metaphysician.

On the other hand, it seems to me possible to give up altogether on the intelligibility of the world in the strong sense I have used here: to declare the question posed by Aquinas unanswerable, or even unaskable. The mind may revolt at such constraint – but maybe the way things are simply is revolting.

So, no, I do not think the Ways provide a knock-down proof of the existence of God, in the sense that they absolutely compel any reader to follow them all the way to the end.

Nevertheless, I do think that the Ways both pose a real question and provide an answer to it, and so make a coherent and powerful proposal for making sense of the world. That proposal is not simply a proposal about some additional fact to be bolted on to one’s existing view of things: it is a proposed articulation of the most basic ways in which the world might be intelligible. (And even the fourth and fifth ways might be part of such a proposal, even if they don’t work as any kind of probative argument.)

Furthere, it seems to me not to be obvious that one can do better than this proposal; that does not simply go without saying.

More than that, though, the Ways lead on (as I have been trying to suggest in the last few posts) to a theological grammar that has a great deal of power. It seems to me that any theology that claims that God is creator needs to take seriously the way of articulating that claim that Aquinas offers: the way in which he gives us concepts with which to speak about the distinction and the relation between God and creatures; the way in which he grounds God’s mystery in the very fact that God is creator, the way in which he re-reads contingency and mutability as creatureliness and gift, and so on. There’s a good deal here that is theologically rich and interesting, and even if my own attempts at theological articulation end up traversing this terrain from rather different directions, I don’t think Aquinas’ Ways can be dismissed simply as a bit of ‘philosophy’ with nothing to say to ‘theology’.

Reading the Five Ways 14

Reading the Five Ways
14. Absolute Dependence

The demonstration of the Five Ways involves God being made evident to the inquirer indirectly. That is, the Ways do not make God clearly graspable and definable; they make God evident only by making the character of the world evident. The Ways teach the inquirer to see the world as an ordered whole, a cosmos – as held together by webs of interdependence. And the Ways teach the inquirer to see this whole cosmos as utterly dependent upon a mystery from which it flows – so that, as it were, she begins to see that the world is patterned by lines of perspective, whose vanishing point remains tantalisingly out of view.

The Ways point to a basic reorientation of one’s understanding of the world. The inquirer who fully internalises the Ways will begin to see the movements and actions of things in the world as the expression of an Activity flowing through them; she will begin to see contingency not simply as mutability and decay but as creatureliness, and as the marker that finite things are gifts; she will begin to see the world as coming from and going to mystery. She will, in other words, begin to see the world as creation.

It strikes me that we are not a million miles from Schleiermacher at this point, despite the vast differences in idiom and philosophical machinery. I’m thinking of Schleiermacher’s discovery of the feeling of absolute dependence woven in to all his active and knowing engagements with the world. Of course, Schleiermacher’s emphasis falls more on this dependence as the thread that holds together the subject in the world, and Aquinas’ emphasis falls more on this dependence as a thread that holds together the world known by the subject, and so (to use the terms in a rather clumsy fashion) Schleiermacher is more psychological where Aquinas is more metaphysical. Nevertheless, there’s a similar intuition at the heart of both accounts, and both Aquinas and Schleiermacher are fundamentally theologians of creation.

Reading the Five Ways 13

Reading the Five Ways
13. The Five Ways as Foundation

I said before that

Aquinas’ central intention in these three articles is … to show how a bridge can be built from knowledge of our world to knowledge of God…. Much of the rest of the Summa then consists of driving all sorts of freight over that bridge, in both directions…. [T]he Five Ways are foundational to his whole project not in the sense that without them he would have to give up on Christian faith, nor in the sense that they everything that follows is unpacked directly from this starting point, but in the sense that the failure of this bridge would mean that the Summa would have to take an utterly different form.

I want to unpack that comment just a little.

It seems to me, as I have said, that the prime point of the Ways in context is not to demonstrate to the sceptic that God exists (though Aquinas certainly thinks that the arguments have the power to do that). Rather, they yield a grammar. Someone who has worked through the Ways (and through the material that immediately follows them) should start manipulating in new ways claims about God and God’s ways with the world.

(In fact, because (a) belief in God is not truly at stake for Aquinas in the Five Ways, and because (b) the Ways lead inevitably to discussion of the manner of God’s existence, there is a sense in which (as I once heard Nicholas Lash say), Aquinas asks ‘Does God exist’ in the same way that one might ask ‘Does the number 2 exist?’ – that is, he asks in what sense it is proper to use ‘existence’ language of God.)

The Ways should prevent the theologian from taking claims about God as if they were straightforwardly, unproblematically descriptive claims. After all, our language is fitted for talking about the world precisely in insofar as it is intelligible – insofar as it can be gripped by thought, brought under concepts, arranged, and spoken. The Ways, as I have been stressing, show that the strings of such intelligibility must be snipped in the case of God, even though it is that intelligibility that itself demands reference to God.

The Ways provide a pair of scissors for snipping the cords that tie our language about God to our grasp.

They also, however, set out the way in which language about God can work. As it were, having knocked over any language about God which tries to stand on its own two feet, they allow it to get up again provided that it can stand upon God’s creation – upon the patterns of God’s ways with the world. The Ways suggest a certain kind of decoding of theological language: claims about God will always be claims about God as the Mystery who has done this or that with the world – ‘God as the beginning and end of creatures.’ (For us, even talk about God’s immanent life is and can only be talk about the life of the God who creates, guides and saves the world.)

These ground rules do not say everything that needs to be said about God. They do not implicitly contain the whole content of theology. They do, however, provide rules by which any theological content can be stated, arranged, and manipulated – how it can form the basis of arguments, rather than remaining as the expostulations of unreasoning faith. The Ways are, for Aquinas, a necessary first step; they make theology possible.

Reading the Five Ways 12

Reading the Five Ways
12. The Ways to mystery

The Five Ways begin with the intelligibility of the world, and end with the assertion that something must end the chains of question and answer that constitute that intelligibility. Implicitly (in a way that his later arguments will make explicit), the same Ways that demonstrate the necessity of some such answer at the same time show that this answer is bound to be deeply incomprehensible. In other words, the Ways are arguments that lead from intelligibility to mystery.

My invocation of ‘mystery’ is here not meant to be any kind of hand-waving resignation of intellectual responsibility. The mysteriousness that stands at the end point of Aquinas’ arguments is a direct consequence of those arguments. When, in the ensuing discussion of the ‘manner of being’ that God is, Aquinas makes his explicit case for the mysteriousness implicit in the Five Ways, he is extremely precise about what kind of mystery he means: he shows that the Ways unavoidably lead us to characterise the answer they point to by a series of negations: this ‘X’ that the Ways point to is not a body, is not composed of form and matter, does not allow us to distinguish its essence from its existence, and so on. Those negations do not simply mean that the ‘X’ we are talking about is unlike anything we have met before; they make it impossible to give any kind of direct, positive description of ‘X’ at all. Without making the nature of X in any way self-contradictory, the Ways snip the cords that hold our ordinary language together. The Ways are, for Aquinas, a rational demonstration that the pinnacle of rational understanding – the heart and summit of our attempt to make full sense of the intelligible world – must be mystery.

I am reminded of a remark by Karen Kilby, in her paper, ‘Mathematics, Beauty and Theology’:

one of the beauties of some theology [is] that it aims to advance our knowledge not by letting us comprehend God just a little bit more, but by making us more aware of the incomprehensibility of God. Theology is at its most elegant … when the mystery of God and the clarity of the theology are directly, rather than inversely, related. Theology does not at its best, or at least at its most beautiful, acknowledge the mystery of God by vagueness in its formulations or half-heartedness in its assertions, nor does it achieve intellectual seriousness by in the end knowing quite a lot about God; at its most elegant, the more precise it is, the more effective it is in presenting us with the ungraspability of God. Part of the attraction of thinkers like Aquinas … is the way in which considerable intellectual resources and rigor are devoted to bringing to clarity the mysteriousness of God…

Reading the Five Ways 11

Reading the Five Ways
11. ‘This is what everybody understands by God’?

Where do these Five Ways get Aquinas? Assuming that the world is ultimately intelligible, in the senses described, there must be some way in which the chains of ‘Why?’ questions stop, some answer that they reach which is an answer of a different kind. We can give this ‘answer of a different kind’ various abstract names: the unmoved mover, the uncaused cause, the necessary being on which all contingent being rests, and so on – and to do so is to do no more than to spell out what an ‘answer of a different kind’ means. We are, Aquinas has argued, looking for an answer that is not itself question begging – and all we know at this point is that there must be some such answer, not what it is, or (in Aquinas’ words) what manner of being it is.

Admittedly, it looks on a casual reading like Aquinas claims rather more than this. The first Way finishes, ‘Hence one is bound to arrive at some first cause of change not itself being changed by anything, and this is what everybody understands by “God”.’ The second way finishes, ‘One is therefore forced to suppose some first cause, to which everyone gives the name “God”.’ The third way simply finishes, ‘One is therefore forced to suppose something which must be, and owes this to no other thing than itself; indeed, it itself is the cause that other things must be.’ The fourth Way, however, finishes, ‘There is something therefore which causes in all other things their being, their goodness, and whatever other perfection they have. And this we call “God”.’ And the fifth: ‘Everything in nature, therefore, is directed to its goal by something with understanding, and this we call “God”.

There are two slightly different ways of understanding what is going on here. One might (and I think with somewhat lesser plausibility) think that Aquinas is here directly addressing the person who believes in God but not in God’s demonstrability. ‘Look,’ he would be saying, ‘I’ve shown that “demonstrability” reaches as far as the existence of a first principle, an unmoved mover, a something on which all else depends… are you really going to tell me that this something is different from the God you already believe in? No, of course you are not: that would be an absurd refusal to use “God” in the way that all believing people do – as the creator of the world, who depends on nothing for his own existence. So, see, your God is demonstrable.’

A more plausible interpretation, I think, is that Aquinas is simply saying, ‘Let’s use the word “God” as a placeholder to name the “something” that these Ways point to, on the basis that “God” has always been the term used for the unmoved mover, the first cause, etc.’ In other words, by using the word ‘God’ here, he is making no further assumptions about what kind of reality this “God” is. The introduction of the name ‘God’ at this point is not an argument; it adds nothing (except some handy terminology) to the conclusions reached by the Five Ways.

Now, in the next section of the Summa, still without going beyond what is strictly contained in the endpoint reached by the Ways, Aquinas will go to go on to ask what it means for something to be an unmoved mover, first cause, and so on. And then, still later, he will go further, and ask whether and in what senses this reality can have applied to it the descriptions that Christians apply to God. In other words, although he thinks he has demonstrated that ‘God’ exists, he does not at this point think he has demonstrated what this God is, or whether it is the same reality as the ‘God’ named in Christian faith.

Of course, were the Five Ways directly addressed to atheist or sceptical readers, this strategy would need to be spelt out rather more clearly. Aquinas would need, perhaps, to do more to justify using the word ‘God’ as a placeholder, perhaps introducing it rather later; and he would need to do more to point out the way in which he is building an argument for the connection between this ‘God’ of the Five Ways and the God of Christian faith (rather than making that connection with a question-begging assertion). The Five Ways are, however, written primarily with an eye to those who already believe in God, but who need to be convinced of God’s demonstrability (and so of the possibility of a certain kind of rational discourse about God) – and so Aquinas’ does not bother to pick his terminology, or to signpost his route, in the best way to assuage sceptical doubts.

If, then, we are to translate Aquinas’ argument into a form suitable for an atheist audience, we might delete his claim that ‘everybody’ will happily use ‘God’ to name the end-point to which the Five Ways point. We might, instead, simply say: ‘Let X be whatever it is that answers these questions without begging further questions. X is the unmoved mover, the uncaused cause, the self-existent cause of existence and so on. Now, what manner of reality must this X be?

(Note, by the way, that we have not shown that each of the Ways leads to the same reality, or that any one of them leads to a single, unique reality. So ‘X’ might name a whole set of realities – and that is one of the possibilities we will have to consider when asking what manner of reality X is.)

All this means, to repeat the point once more, that the Five Ways are radically incomplete on their own. Only if you carry on into the much longer and much more detailed arguments in Questions 3 to 11 of the Summa – the doctrine of divine Simplicity, and what follows from it – do you find Aquinas discussing the kind of reality that his proofs have demonstrated. And so only if you carry on into that material can you judge whether Aquinas is right to call it ‘God’.

It is probably worth saying here that if the arguments in Questions 3 to 11 show anything, it is that any reality that answers the questions posed in the Five Ways (without itself begging further questions) is going to be a very, very strange reality indeed – and one that is extremely difficult to talk about directly. Whatever ‘X’ is, it is not a reality that fits easily into any of our categorisations, or onto any of our lists: it is not in any sense going to be just one more ‘thing’ (albeit a rather special thing) in the list of things that there are. But that’s another story.

Reading the Five Ways 10

Reading the Five Ways
10. The fifth Way

I don’t have a great deal to say about the fifth Way. It is not quite the standard ‘design argument’, but it is not very far off. It focuses not on the supposedly inexplicable way in which animals are put together, but on the fact that the world is full of things that act so as to achieve some end, and do so successfully. Things, as it were, act not only as if impelled from behind, but as if drawn from in front – and yet most things have no capacity to see, understand, or otherwise take into account what is in front, and so that drawing must be something that is given to them by something that can ‘take into account’ – something intelligent.

DarwinYou are standing in a field and are startled when, one by one, ten arrows shoot past you. Seven of them hit a nearby target; two undershoot; only one misses wildly, parting your hair and burying itself in a nearby tree. Whilst you can explain the movement of the arrow through the air by reference to the laws of simple projectile motion, you guess that something other than, say, a random explosion has hurled these arrows into the air: there is nothing that could ‘draw’ them towards the target so consistently unless they had somehow been aimed. There must be some being with a capacity to take the target into account – a capacity to aim – somewhere in the process.

The trouble is, of course, is that in the case of natural goal-directedness there are processes of which Aquinas could not have dreamt, processes that can ‘take into account’ the target without any kind of intelligence. I may be missing the target myself, but I’m pretty sure that Darwin has done for the fifth Way.

Reading the Five Ways 9

Reading the Five Ways
9 The Fourth Way

The fourth Way is the hardest for a modern reader to make sense of, because it relies upon aspects of Aquinas’ worldview that don’t have strong echoes for a typical modern audience.

Like the first three Ways, the fourth relies upon a form of intelligibility that Aquinas thinks we find in the world. We properly arrange things into hierarchies of ‘more’ or ‘less’ (things are taller or shorter than one another, heavier or lighter, nobler or less noble, better or worse, and so on). And Aquinas takes it as read that there are certain crucial hierarchies which work in a special way – where to say a thing is ‘more x’ or ‘less x’ is to compare it to some reality which is fully x.

I say that Aquinas ‘takes it as read’. He doesn’t argue for this point; he simply states it, using Aristotelian terminology to articulate a basic conviction that he thinks his readers will (perhaps inarticulately) share.

sunWe are not those readers, and this claim sounds very strange in our ears. You can get a sense for it, though, by thinking about heat. You can, perhaps, imagine a worldview in which all heat in the world was believed ultimately to be derived from the sun, either as a direct result of the sun’s heat warming something up, or because the sun’s heat had somehow been stored in things to be released when they were burnt (or by some other process). If you saw things in this way, you might well regard claims about things on earth being more or less hot as involving the placement of those things somewhere on a scale that ran all the way up to the sun: ‘heat’ would, for you, mean ‘likeness to the sun’.

Aquinas is, of course, not really interested in whether this is true of heat. Rather, he speaks of truth, goodness and nobility. He suggests to his readers that at least these attributes – which, as we shall see, are rather special – work in the way he is describing. Nevertheless, he still doesn’t argue the point: this is, as I read it, Aquinas trying to draw out and articulating aspects of what he thinks his readers will already know. That is, he thinks his readers will readily agree that one of the ways in which the world is intelligible is that the things in it are arranged into hierarchies of value, being more and less good, more and less true, more and less noble, etc. And he thinks he can rely upon his readers to agree, without much fanfare, that things in the world are more or less good, noble and true to the extent that they resemble some reality that is superlatively Good, or superlatively Noble, or superlatively True.

He then does two things – and it is at this point that he is, I think, actually trying to build something on the ground he shares with his readers, rather than contenting himself with uncovering that ground. First, he tells his readers that these attributes are indeed rather special. There is, Aquinas believes, an intimate connection between goodness, truth, nobility, and being. He believes (with Aristotle’s support) that the scale on which things are more or less true (or good, or noble) is intimately tied up with a scale on which their existence, their being, is more or less fully realised. That is, he believes that things that are less true (or good, or noble) are in some sense deficient in being. So the scales of goodness, nobility, truth, and being are not independent scales (mutually perpendicular axes marking out a conceptual space in which the objects of the world sit) but aspects of a single scale. And what is true of the individual aspects of this scale must a fortiori be true of the scale itself. Things are (and so are good etc) to a greater or lesser degree, precisely to the extent that they resemble a reality that fully is (and so is fully good etc).

Second, he reminds his readers (again, with Aristotle’s help) that, in this sort of hierarchy, the superlative reality (e.g., the sun) is not simply the standard by which all other things are measured (e.g., as more or less hot) – it is the cause of their position on that scale (i.e., things are more or less hot because the sun has heated them to some degree or another). So if there is indeed a fully-realised being which is wholly True, wholly Good, wholly Noble (as his previous point suggested), that being will be the cause of whatever nobility, whatever goodness, whatever truth, whatever being there is. And that, at last, is the point where Aquinas has been headed all along with this fourth Way: to the idea of a fully realised being which is the cause of all other being. Where he ends up, in other words, is not that different from the point that the previous three Ways led to.

The compressed argument of this fourth Way is addressed to those who already think in an explicitly or implicitly Aristotelian way. In fact, Aquinas does not argue very much at all in it. He simply refers the reader to a few ideas of which they ought to need no convincing (the idea that certain kinds of hierarchy of value involve relation to a superlative that is the measure of the hierarchy, the idea that the superlative of such a hierarchy is the cause of whatever in other things approximates to it, and the idea that being is closely related to goodness, truth and nobility). And the only argument he mounts consists in putting these ideas together, rather straightforwardly, to yield the conclusion he has been aiming at.

Now, for those of us who do not automatically share his starting point, it might nevertheless be possible to argue for this way of seeing things – to demonstrate that (despite our doubts) there is truth in the ideas on which Aquinas builds in this Way. For a modern readership, however, in the absence of such a demonstration, these ideas are likely to seem like they belong somewhere on the road between implausible and nonsensical. For this reason the fourth Way is, I think, the hardest of the Ways to resurrect.