Category Archives: Aquinas

Reading the Five Ways
8. The third Way

In the 1980 film Somewhere in Time, a young actor is handed a pocket-watch by an elderly female stranger. He later discovers that she had been a famous actress decades before, and (this being cinema) discovers a way to travel back in time to meet her as a young woman.

When he finds her, he gives her the same pocket watch that she (decades in the future) will give back to him. The watch therefore ‘loops’ around in time. There’s no point at which it is manufactured: it simply is. And yet there is something deeply odd about that, and you can’t help feeling that the watch’s existence is unintelligible.

If, when watching the film, you feel that sense of unintelligibility, Aquinas (like an old-style cinema usherette) will be there to offer you some concepts for making sense of that feeling. (But please remember: the concepts that he offers have nothing to do with Paley’s design argument: that was a different watch altogether).

The watch, Aquinas would say, is contingent, in that it is quite possible that the world could have contained no such watch; it is possible for the watch not to be. And yet the watch is, and therefore there must be some reason why it is – even if (in this imaginary case) we can’t quite get that question into a straightforward causal and temporal form.

This is brilliant stuff – but there is a real problem in Aquinas’ way of weaving these concepts into his third argument. He sets up the idea of contingent existence (the existence of things that need not exist, whose existence requires explanation; things whose existence depends on something other than themselves) – and so seems to have set up the possibility of yet another kind of ‘chain’ linking the facts of the world into intelligible order. But in the event, Aquinas does not run a version of the argument he has used in the first two Ways. Instead, he says

a thing that need not be, once was not; and if everything need not be, once upon a time there was nothing. But if that were true there would be nothing even now, because something that does not exist can only be brought into being by something already existing. (1a.2.3)

I’ll leave the translation, interpretation and criticism of that version of the argument to the experts (you know, the people who actually know what they’re talking about). It seems to me that, instead of following the details of Aquinas’ presentation, we can take this third Way as a regression just like the first two – and, if we do, I think it provides the most powerful argument of the three, because it asks the most basic ‘Why?’ question of all. Faced with some reality in the world, it doesn’t ask, ‘Why does this change in the way that it does?’ nor ‘Why does it act in the way that it does?’ but ‘Why is it there at all?’

The third Way recognises that nothing in the world is sufficient in itself to answer all the questions we might have about it – so some of our questions will always take us beyond the object in question. And it recognises that the world itself is insufficient to answer all our questions about it. The world leaves us asking, at very least, Why is there something rather than nothing? – and (to Aquinas at least) the world does not seem itself to be capable of providing any answer to that question.

Reading the Five Ways
7. The Second Way

The Second Way covers very similar ground to the first. Instead, however, of focusing on ‘motion’ (i.e., change), and the dependency involved in it – i.e., instead of focusing upon the fact that each link in a chain needs to be suspended from some other link above it – Aquinas shifts his focus onto the active causal relationships that hold the chain together – i.e., he shifts his focus onto the way in which the links of the chain hold on to one another.

At the same time, his discussion takes a step that seems to take us towards greater abstraction: ‘cause’ seems to cover a wider conceptual territory than ‘motion/change’. Certainly, when faced with some event in the world, we can ask ‘Why did that happen?’, and the answer we give does not necessarily itself have to take the form of an event or happening.

This is perhaps the Way most clearly connected to my earlier descriptions of Aquinas’ belief in the ‘intelligibility of the world’. Aquinas is, in effect, sketching a world in which it is always possible to ask ‘Why?‘, and always certain that there is an answer – even if that answer should be one that we have not found, and even if for some reason it should bee an answer that we will never find. Once again, the concepts he wields allow him to start articulating the intelligible texture of the world.

This second Way is, I think, easier than the first to translate into the twenty-first century – but it is also true that strange things happen when we try. Suppose I ask, ‘Why is that stone falling?’ and you reply ‘Because it has fallen off the ledge, and is no longer supported by anything, and because unsupported objects that are heavier than air do indeed fall.’ Things will remain fairly straightforward if I go on to ask, ‘Why did it fall off the ledge?’ and get the answer, ‘Because it was hit by this cat.’ It’s easy to imagine us getting into quite a long chain of questions and answers heading backwards from that point. But what happens if, instead, I ask, ‘Why do unsupported objects that are heavier than air fall?’ Your answer will probably cite the law of gravity, and then we’re going to get into all sorts of questions about why the law of gravity takes the form that it does, and why there is a law of gravity at all.

In other words, if we pursue this causal chain, we will rather quickly (at the top of a rather short chain) get into apparently imponderable territory. Even if the details of the law of gravity can be made to drop out of some deeper, more unified theory of the universe, it seems to me that, if I keep asking ‘Why?’ as we travel up this chain, you are pretty quickly going to face the temptation to shrug your shoulder and say, ‘Well, that’s simply the way things are.’ And that, I think, brings us to Aquinas’ third Way.

(You should remember, by the way, that is not quite the direction that Aquinas takes in his second Way: it is, rather, my attempt at translation – at developing a similar argument in our own terms to the one that Aquinas mounts in his thirteenth-century terms. The whole idiom in which I can speak about ‘the law of gravity’ and the like would, I think, be foreign to Aquinas.)

Reading the Five Ways
6. The First Way

I can’t in good conscience conduct a detailed discussion of Aquinas’ Five Ways without – well – giving a detailed discussion of the Ways themselves. So in the next few sections I will go through each Way in turn. You can, however, quite easily find plenty of more detailed accounts that do exactly the same, and I don’t think what follows is particularly original – or, indeed, particularly interesting. If you’re bored, skip along to part 11, where my own argument about the import of all this for Aquinas (and for us) gets going again. However, for the sake of obsessive completeness, here goes.

The first Way in which Aquinas’ philosophical concepts help him to articulate his vision of an intelligible world focuses on motion – or, to be more accurate, change. He is enabled to see the world as an interlocking system of changes: of movements, of alterations, of flourishing and decay, of comings-to-be and passings-away. And he thinks that whenever you see some such change, you are seeing a form of dependency: you are seeing something that is somehow not simply changing, but being changed. He thinks, in other words, that when faced with any change, you can ask ‘Why?’, and expect an answer other than the change itself – in fact, an answer that will involve some other change. And the fact of such dependency means that all those changes can be arranged into chains, and that Aquinas can launch the kind of argument described above: demonstrating the necessity that the chain have an end-point.

By the way – if you find Aquinas’ philosophical terminology daunting, you might like to know that the First Way has been set (in outline) to music, in the second verse of Abide With Me:

Swift to its close ebbs out life’s little day;
Earth’s joys grow dim, its glories pass away;
Change and decay in all around I see:
O thou who changest not, abide with me!

If you want to get a clear mental picture of what the first Way says about the world, it is worth noting that the chains that Aquinas joins together are not necessarily in themselves temporal (even though each link in the chains is itself a temporal change). Aquinas is not presenting a picture of each new change depending upon some other change that took place some time before. Rather, he pictures the world as something more like a clock: the hands move because the spindle they are attached to moves; that spindle moves because this cog moves; this cog moves because that one does; that one does because the escapement mechanism moves; the mechanism moves because the pendulum moves: the clock as a whole is an ordered set of interlocking movements and dependencies.

This picture may seem clear enough, perhaps even compelling, but to translate it fully into contemporary terms turns out to take some real labour. That’s because our understanding of motion has changed (strange though that might sound), and, even if we restrict ourselves to motion in the most straightforward sense (movement through space), the kind of dependency that Aquinas sees is more evident to us in acceleration (change of motion) than in uniform motion per se. (You may recall that Newton’s First Law – a decidedly non-Aristotelian piece of work – says that ‘Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it.’) From acceleration, we therefore quickly enter a conceptual world not of motion–dependent–upon–motion, but of motion tangled up with force, and so with energy, with fields, and with the whole paraphernalia of modern physics. Before very long, we’ve reached territory where the path of Aquinas’ argument becomes rather indistinct.

So, although for Aquinas this first Way is the ‘most obvious’, and although it is still initially easy to grasp, it does rather run into the sand as it crosses from Aquinas’ century to ours. Aquinas’ concept of ‘motion’ is already pretty general, but I think we need to take a further step in the direction of abstraction if we are to keep Aquinas’ show on the road. Fortuitously, that is precisely what Aquinas’ second Way seems to me to do.

Reading the Five Ways
5. Using Aristotle

Aquinas is able to see his world as an intelligible one because he looks through a lens polished by certain concepts. Those concepts help him articulate the world’s intelligibility.

That is, Aquinas has learnt a set of concepts that allow him to see how one link can be connected to another link, and which therefore help him to see what was previously a pile of unconnected and heaped rings as a collection of coiled chains. He has learnt those concepts in large part from Aristotle – though they have since Aristotle’s time been through a long process of transmission that has refined and rearranged them, and Aquinas himself is by no means uncritical of his inheritance. Those refined Aristotelian concepts provide, in Aquinas’ thirteenth century, an astonishingly powerful way of asking and answering questions about the world.

Aquinas in his Five Ways uses this set of concepts to give content to his basic intuition about the intelligibility of the world. Each Way in its different idiom says: Look, here are the kinds of ways in which the world is linked together into an intelligible whole; here are some of the basic ways in which unruly facts are joined together into chains that we can grasp and tug; what happens when we follow those chains upwards?

Now, Aquinas’ context is not ours, and we no longer habitually use Aristotelian scalpels to conduct our vivisection of the world. That’s not simply a matter of ‘science’ having moved on: a lot of the concepts that we’re talking about are not, in our terms, ‘scientific’ at all: they’re metaphysical, and the ways in which metaphysics has moved on are much less obvious than the ways in which ‘science’ has moved on. Nevertheless, things have moved on, and any attempt to make contemporary sense of Aquinas’ Five Ways is bound to involve some kind of translation. That is, it is bound to involve trying to understand how his arguments worked in terms of the concepts and intellectual practices of his own day, and then see whether we can reconstruct some kind of similar argument using the concepts and intellectual practices of our own.

That’s not because Aquinas was backward, and we are not; it is because he, like us, lived in history. Anyone reading my words, or Richard Dawkins’, in 750 years time (now there’s a thought) will have to perform some similar form of translation if they want to follow and judge our arguments, and there is no way we can predict the ways in which our lines of thought will lie at a tangent to their patterns of common sense and intellectual discourse.

Reading the Five Ways
4. The intelligibility of the world

Imagine that you were walking across a foggy field, and suddenly found an iron chain dangling in front of you. The fog prevents you from seeing very high, but it is clear that the bottom link of the chain is dangling a foot or more above the ground. You can see that the bottom link is suspended from the second, the second from the third, and so on up to about the fiftieth – which is as far as you can see. You know, however, that the fiftieth link up must itself be suspended from something – and the chain seems securely suspended when you tug sharply downwards on it. Curious (and foolhardy), you climb a little way up the chain, and find that the fiftieth link is indeed suspended from the fifty-first, the fifty-first from the fifty-second, and so on and so on, as far up as you feel capable of climbing. You let yourself carefully back down to the ground.

If you were anything like Aquinas, even though you can’t see far into the fog, you would think it clear that had you been able to go on climbing, you would at some point have had to reach something which was not simply another link in the chain: some method or means of suspension of a different kind. You would think that the discovery of yet another link, or of any number of links, would not really count as an answer to your initial question: ‘Just what is holding this thing up?’

So, if you were anything like Aquinas, you would think it clear that at some point (you cannot say how far up) you must be going to encounter something that, unlike any given link in the chain, does not require you to ask what it is suspended from. You might speculate: perhaps it will be the outstretched arm of a crane which itself is resting upon the same floor from which you have climbed; perhaps it will be a wire strung between two nearby buildings. Or perhaps something more unusual: is the chain as a whole held up by some bizarre magnetic field? Or is it – I don’t know – held up by gravity at the Lagrange point between the earth and the moon? Who knows. Any kind of explanation which allows us to stop asking what the next link in the chain is suspended from will do.

The alternative would be that at some point you would simply come to the top of the chain, and find that your grasping hands closed on empty air, not because you have missed something (some other explanation, some other form of suspension) but because that is all there is, arbitrarily and incomprehensibly.

Or perhaps you would find that you could simply climb on up forever, which is another kind of arbitrary incomprehensibility. One link is no explanation, two links is no explanation, a million links are no explanation: to carry on discovering more links provides no explanation, even though one carry on forever.

So, either the world is radically incomprehensible – or, if the world is at all intelligible, then at some point there must be some kind of answer to the ‘What is this suspended from?’ question that does not simply consist in the identification of a set of higher links – an answer of a different kind. The assumption that there must be some such an answer – even if the fog should be so thick, or the chain so long, that we will in fact never discover it – is the assumption that the world is intelligible: that, at some level, the world makes sense.

In putting forward at least the first three of his Five Ways, it is this intelligibility of the world that provides the ground upon which Aquinas takes his stand.

There are two connected senses in which his ‘proofs’ trade on that intelligibility. In the first place, faced with the baffling complexity of things – their strange interlockings, the odd patterns of action and interaction that knot them together – he believes that we have a strategy to pursue to make sense of them. We can ask Why? – and we can go on asking it, doggedly and persistently, worrying away at the world like a terrier until it yields answers. We can be like a three-year-old, refusing every to stop with any partial or questionable answer offered to us, instead always and again asking, ‘But why?’ We may not yet be able to answer some of those questions. There may be some why questions that we will, in fact, never answer – questions whose answers are in some way beyond our capacity. But we can always go on asking, with a basic trust that even if we don’t know it yet there must be some kind of answer.

In the second place, however, Aquinas believes that things only truly become intelligible, and we only truly provide explanations, if the chain of answers that our questioning tugs on is suspended from some kind of end point. It may be beyond our present understanding; it may remain beyond our understanding – but if the world is at all intelligible, there must be some such end point. We trade upon that assumption, Aquinas thinks, every time we go around insistently tugging on chains.

Remember, however, what I said in the last section about the emptiness of the Five Ways. Aquinas says nothing in this section of the argument that tells you what this end-point must be, except what is bound up with the very idea of an end-point: it must be (in terms of my chain analogy) a something from which things are suspended that is not itself suspended from anything, a something that does not need to be suspended from anything: the chain can only stop at an unmoved mover, a first cause, a something whose existence depends on nothing but itself. In other words, the only content that he provides at this point – the only thing that he thinks the Five Ways prove – is that there is some kind of end-point which isn’t itself just another link in the chain.

(Yes, I realise that it looks like Aquinas does say more than that – but I’ll come back to that in a later section.)

Note two final things at this point. First, Aquinas’s assumption is not about our power to understand the world fully, to trace the chain all the way back to the source. Fundamentally, his assumption is about the world, not about our minds. Everything connects: the world is articulated – and that is why we can go on asking ‘Why?’.

Second, the full intelligibility of the world requires a transition from one kind of question to another. In Aquinas’ terms, the world’s intelligibility is a matter of both physics (the science of the chain links) and of the science of what comes beyond physics: metaphysics.

Reading the Five Ways
3. The emptiness of the Ways

In the first article, when arguing that ‘the awareness that God exists is not implanted in us by nature in any clear or specific way’, Aquinas uses the following analogy. ‘[T]o be aware of someone approaching is [not necessarily] to be aware of Peter, even if it should be Peter approaching.’ (1a.2.1 ad 1) In the terms of that analogy, the Five Ways are arguments that say, ‘Stop! Listen, someone is approaching!’ rather than arguments that claim to demonstrate who it is who is approaching. Rather than answering a question, the Five Ways pose a question that is only answered by subsequent Questions – and then only in rather indirect ways.

The article before the Five Ways article, which asks whether the existence of God can be made evident, explains this in some detail – though in rather abstruse terms. It explains the kind of ‘demonstration’ that is about to be offered.

Aquinas begins with one kind of ‘demonstration’. Suppose we are trying to demonstrate that Columbine will bring Arthur out in a red rash. Columbine is a cat, we might say, and all cats bring Arthur out in a red rash, so Columbine will indeed bring Arthur out in a red rash. Such a demonstration (Aquinas calls it a ‘demonstration why’ – a demonstratio quae) works because we have access to some kind of definition of the subject of the demonstration: we know what Columbine is. Such a demonstration involves, in fact, the arranging of what we already know – of what is already familiar – into an ordered whole.

In the Five Ways, however, we are faced with a different kind of demonstration – a ‘demonstration that‘ (demonstratio quia). Arthur has suddenly come out in a red rash, we say; there must be something – some rash-causing thing, some irritant – that has caused it. More slowly: we note that Arthur is red; we recognise that this redness is the effect of some cause; we decide to use the word ‘irritant’ to name something that causes this kind of redness; we infer that there must be some such irritant, because Arthur has indeed gone red – and we can then go on to ask other questions about this irritant. We don’t know what kind of thing the irritant is, except that it is a redness-causing thing. To say ‘there is an irritant’ is in an important sense empty: it does not tell us what we’re looking for (cat hair? an embarrassing joke? dust mites? sulphur dioxide? stress? the realisation that his flies are undone?), simply that we are indeed looking for a red-making thing of some kind. This kind of demonstration does not arrange what we already know; it shows us the limits and gaps in what we already know, and challenges us to fill them.

Just so, the Five Ways (when we finally get to them) are in effect going to say: looking at the world raises certain kinds of question. Let’s call the answer to those questions, whatever it is, ‘x’. X must exist, even though (at this point in the argument) we have no knowledge of what x is, other than it is the kind of thing that answers these questions. As Aquinas puts it in 1a.2.2 ad 3 ‘God’s effects, therefore, can serve to demonstrate that God exists, even though they cannot help us to know him comprehensively for what he is.’ As I said earlier, they are a way of saying ‘Listen! Someone’s coming’ rather than a way of telling us precisely who is coming.

It is only in the next set of Questions, after the Five Ways, that Aquinas will turn explicitly to asking ‘what manner of thing’ this x is, asking what would have to be true of x for x to count as an answer to the questions that the Five Ways have raised. Anyone who treats the Five Ways on their own, and then tells you that they are question-begging, is (on one level) absolutely right; that’s the point. On another level – well, you might want to choose a different guide.

Reading the Five Ways
2. Who is Aquinas trying to convince?

The Five Ways do not appear right at the beginning of the Question ‘Whether there is a God’. They come in the third article, and it is important to read the other two on the way.

The first article argues that it is not self-evident that there is a God: we are not innately aware of God, and (against the claims of theologians like Anselm – of whom more another time) the existence of God does not follow simply from the definition of the word ‘God’. (Alongside these two denials, there is a third (1a.2.1 ad 3), of an argument about the undeniability of the existence of truth. This seems to me to be one of those many occasions when Aquinas has included an argument in an article simply as a make-weight, or as a jeu-d’esprit. I can’t see that either the posing or the refutation of this argument contributes materially to the article.)

The second article, working within the space opened up by the first, argues against those who say that the existence of God, not being self-evident, should simply be accepted on faith. No, says Aquinas, it is possible to demonstrate the existence of God. It is not directly evident that God exists, but it is possible to make it evident by looking at the world that God has made.

The third article then tries to fulfil the promise that this second article has made: it aims to show us how the existence of God is in fact demonstrable, by working from things we know about our world.

If these three articles are taken together, I don’t think it is quite right to say that the existence of God is at stake in Aquinas’ third article, even though that is how the third article itself is apparently framed. By this I simply mean that if Aquinas’ arguments in the Five Ways should fail (and if he should be unable to repair the failure) he would be failing to fulfil the promise made in his second article, and so would be thrown back on the idea that God’s existence can only be accepted by faith. After all, his argument in the second article is not that there was something wrong with accepting God’s existence on faith, simply that something more than that was possible and appropriate. (At one point in the second article he says, in the course of making a slightly different point, ‘there is nothing to stop a man accepting on faith some truth which he personally cannot demonstrate, even if that truth is such that demonstration could make it evident.’ I am suggesting that, for Aquinas, there is nothing to stop him accepting on faith the existence of God, should he fail to demonstrate it, even if that is because it is finally indemonstrable.)

If this is right, the Five Ways matter to Aquinas not, I think, because his belief in God rests upon them, but rather because a certain way of pursuing rational understanding of God rests upon them. To put it another way: Aquinas is not, I think, directly addressing those who think that the only possible way in which belief in God could properly arise is if the Five Ways (or some argument like them) work and so give reason to believe to people who should otherwise firmly reject the idea of God. He is addressing those who think that there is no need for such a demonstration, because they already believe in God and see no need for further supports.

I am not suggesting that the Five Ways are not meant as a real demonstration of the existence of God. That is, I am not denying that the Five Ways are an attempt at a demonstration that starts from the kind of knowledge of the world that might be shared by the other kind of addressee – a sceptic or atheist, for instance. Nevertheless, I am suggesting that if we are to extract from the Five Ways an argument addressed to a sceptic or atheist, we will have to do some translating. That’s going to have to remain as a cryptic comment for now, but I promise I will unpack it further when the time comes.

I think, by the way, that we can already give an initial answer to one of the questions I posed in the last section, about the precise sense in which Aquinas’ argument begins with this material on God’s existence. Aquinas’ central intention in these three artices is, I think, to show how a bridge can be built from knowledge of our world to knowledge of God; that’s what it means to show that God’s existence is demonstrable. Much of the rest of the Summa then consists of driving all sorts of freight over that bridge, in both directions (remember once again Aquinas’ overall purpose for the Summa is to ‘make God known … as the beginning and end of all things.) If this is right then the 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.

Okay: when I said that I was going to devote one post to Aquinas, I may have been underestimating…

Reading the Five Ways
1. Putting the Ways in context

In order to understand the Five Ways, one needs to pay attention to their context in Aquinas’ Summa Theologiae. Many misreadings of Aquinas’ argument (and, in particular, many drastic oversimplifications of it) arise from extracting his presentation from the wider ‘Question’ (i.e., ordered discussion of a particular topic) of which it is a part. The discussion of the Five Ways forms the body of one ‘article’, but there are three such articles in the Question as a whole. And that Question is itself one of a set of three that together make up a significant sub-division of the Summa as a whole. (See the diagram below.)

So, when introducing this material, Aquinas reminds us that the overall purpose of the Summa Theologiae is to ‘make God known, not only as he is in himself, but as the beginning and end of all things…’. He then tells us that the first main topic that must be examined as he pursues this purpose is ‘the nature of God’, and that there are three questions to be asked: whether there is a God (an Deus sit), what manner of being God is, and what we can say about God’s knowledge, will and power.

The first of these questions, ‘Whether there is a God’, is itself divided into three sub-questions (‘articles’): Whether it is self-evident that God exists, whether it can be made evident, and (finally) whether God exists. It is best not to skip to the third of these articles straight away, because just as the three larger questions belong together, so too do these three articles only really make sense together.

Two points are worth bearing in mind at this point. First, despite Aquinas declaration that the purpose of the Summa is to ‘make God known, not only as he is in himself, but as the beginning and end of all things…’, you should resist the temptation to think that this material (the initial block of three Questions) contributes simply to the ‘God … as he is in himself’ aspect of that purpose, and that we might expect only at some later point to turn to God ‘as the beginning and end of all things’. As we shall see, things are not so straightforward.

Second, you should be beware of making any hasty assumption about the way in which this material on ‘the nature of God’, and more specifically on the question of God’s existence, comes ‘first’ in Aquinas’ presentation. One kind of interpreter might say that this is simply a convenient arrangement, a presentational or pedagogic device. The topic in question is, this kind of interpreter might say, simply one of the questions that has come up in theological discussion, and Aquinas had to put it somewhere once he had decided to address it. Another kind of interpreter, however, might say that this Question establishes the starting point from which the rest of the content of the Summa is deduced or inferred, such that the rest of the Summa is simply an unpacking of the implications of this first point. Far from deciding to put this Question first out of convenience, this second kind of interpreter would say that this Question simply had to come first. (After all, Aquinas does say in the sed contra of 1a.1.2 that ‘one must be able to demonstrate that God exists … for knowing whether a thing exists is the first step towards understanding it.’) Later on, I will be suggesting my own interpretation, though I don’t mind telling you now that I will be leaning some way towards this second camp of interpreters, without actually joining them.

NB – all quotations are from the 1960s Dominican translation, now reissued by CUP.