It is a sound rule of academic prudence to admit oneís ignorance promptly when oneís chances of disguising it are slight. Thus I had better begin this chapter by saying that I donít think I understand the Fourth Way, and have even less confidence in my ability to make it out as an argument that proves the existence of God. I console myself by the consideration that I am in good company: both Kenny and Geach seem to give up on the Fourth Way. But since a book with a title or sub-title something like Four out of the Five Ways in the context of St Thomasís theory of science would have attracted yet fewer readers than one entitled or sub-titled The Five Ways of St Thomas in the context of his theory of science I shall make bold to offer the reader some considerations about the Fourth Way, in the hope that the Advertising Standards Authority will thus be encouraged to treat my publishers leniently.
In things we find that some things are more or less good, or true, or noble, and other such things.
That which is said to be greatest in any kind causes everything of that kind,
As usual, the indentation is supposed to indicate something of the structure of the argument, but I offer this with even less confidence than on other occasions. If the indentation is correct, we have the following structure to the argument:
2. There is, then, something which is most true, and best, and most noble, and which therefore most exists: for those things which are most true are most existent.
3. That which is said to be greatest in any kind causes everything of that kind.
4. Therefore there is something that is the cause of the existence and the goodness and of all perfections in everything: and this, we say, is God.
This we should not perhaps be surprised at, since we have seen how St Thomas sees a close relation between the realm of truth and the realm of existence, and sees the former as in some way derivative from the latter. To stop to argue around the validity of the notion of the metaphysical transcendentals would perhaps require another couple of books, books which I am sure I am incapable of writing: so perhaps we can just take this notion on trust tentatively for the time being, and see whether it helps us make progress with the Fourth Way.
An important part of the doctrine of the transcendentals is that of their "convertibility" with existence. ("For those things which are most true are most existent, as it says in the second book of the Metaphysics", as it says in this text.) That is, that which is e.g. good also exists, and that which exists is also good; it is good to the extent and in the way that it exists, and it exists to the extent and in the way that it is good. Hence e.g. something that exists per accidens will only be good per accidens. A clearer and perhaps more obviously acceptable example might be that that which exists per accidens (an ens per accidens) will also be one and the same thing per accidens (unum per accidens). This brings us close to the Quinean principle of "No entity without identity", and makes the whole doctrine of the transcendentals a little less bizarre.
However, the next point of the argument does look bizarre: the claim that there are degrees of existence which correspond to the degrees of the other transcendentals. One might wish to admit degrees of goodness or nobility; but the notion of the truth of a thing is one which we would immediately reject, and we would also reject any connection between degrees of this or that quality and degrees of existence. But again the doctrine can be, if not defended, at least sketched out in a way which makes it less obviously unacceptable. Take for example the question of the truth of things. To the average contemporary English-speaking philosopher, there can no more be a truth of a thing than there can be a meaning of life. But the fact that the average first-year student of philosophy feels that his or her lecturers are missing something when they insist in their rather literal-minded way that life does not have a semantic structure and therefore cannot have a meaning, may encourage us to look for an understanding of the notion of the truth of a thing.
The medievals defined truth in a number of ways, but the most favoured was "adaequatio rei et intellectus", the match of mind and reality. A match is a match, and if A matches B, then B matches A; but there is always a question of onus of match. Generally, when we look out on the world and talk about it, the onus is on our mind to match up to reality. But this is not always so. When we act or speak or make some production, we can condemn the action or utterance or production as being in some way false if it does not match our mind, our intention. The onus of match here is reversed. (It is worth noticing, by the way, that there is no doubt that it was this sense of "true" and "false" which was uppermost in the minds of the Greek philosophers, and they had a struggle to develop the more abstract sense in which sentences on their own are true independently of the mind of their utterer. That is why when Aristotle and Plato want to talk about truth and falsity in an abstract sense they very often talk of "is and is not".)
So much for the different ways in which the human mind and reality have to match: the onus is on the human mind to match the reality it observes, and the onus is on the reality we produce to match the human mind. But the human mind, for St Thomas, is not the only, nor the most important mind. What of Godís mind?
The whole world is Godís production, and so the relationship of the whole world to Godís mind is analogous to the relationship which exists between our own mind and our productions or performances. That is, the onus of match is on the world: it is up to the world to match up to Godís mind, and in so far as it does so, it will be true, in this sense.
But how can the world fail to match up to Godís mind? Presumably only in virtue of some defect: and a defect, as we learned earlier, is an absence of some real existent or existence. The doctrine is beginning to look a little less odd.
But what of degrees of existence? Geach has pointed out that we can find at least one good and clear example in which something may exist to different degrees without any substantial, substantive or qualitative change: that of sound. A note may be sung or performed at a greater or lesser volume; it may, indeed, swell or diminish or die away entirely. The ceasing to exist of the note is no more than the diminution to zero of the intensive magnitude of the note; and since there is ex hypothesi no qualitative change in the note thus performed, what are we to say except that the note, when louder, exists to a greater degree, and when softer, exists to a lesser degree, until perhaps it ceases to exist at all?
Kenny has pointed out that this example is a pretty isolated one: Geach has retorted that it doesnít matter how isolated it is, it shows that the doctrine makes sense. If we are to get any further forward with the Fourth Way we will have to accept Geachís point, at least tentatively, and admit that there seems to be some sense in what is said here.
Unfortunately it seems to me that at this point we begin to run out of possibilities of understanding. It looks as if feature X in this Way is "having a perfection to a limited degree", or perhaps, if we bring forward the account of the convertibility of the transcendentals with existence, "existing to a limited degree". As a feature X in use in the alleged structure of one of the Five Ways, whatever displays this feature will require an explanation in terms of its relation to something different, and I cannot for the life of me see why this should be. Indeed, the use of this feature X presents an extremely curious contrast with the Third Way. In the Third Way it appeared that the feature X which required an explanation was, more or less, "possessing existence to a (temporally) unlimited extent"; while here it is "possessing existence to an (intensively) limited degree" which apparently requires explanation, according to the mind of St Thomas.
Nor does this feature X inspire confidence as one which has the other mark which a feature X must have for the purposes of this type of argument. This other mark is that of generalisability. A whole which contains parts in process of change is itself something which is in process of change, as we saw in the First Way. A similar point could be made with regard to the Third Way: a whole which contains parts which are either perishable or derivatively everlasting is itself something which is either perishable or derivatively everlasting. But is it the case that a whole which contains parts of limited perfection or limited existence is itself something of limited perfection or limited existence?
Taking the word "perfection" in its more familiar English sense of "complete goodness" the point might be made out, provided that we accept a very sound medieval principle, frequently cited by St Thomas, which appears to have originated with the distinguished scholar who is now known by the rather splendid name of Pseudo-Dionysius the Areopagite. The principle is "Bonum ex integra causa, malum ex quocumque defectu": a thing is good if everything about it is good, and bad if anything about it is bad. This thesis about the asymmetry of good and evil is clearly true. For my dinner-party to be a good one, I have to provide good materials and prepare them well. No matter how careful the cooking, the dinner will be a failure if I have stocked my larder with what I have found in the bins at the back of Pricerite; and no matter how expensive or carefully chosen the provisions, my guests will feel somewhat cheated if I have just thrown the whole lot into the oven at Gas mark 7 for a couple of hours. I remember hearing Mrs Foot appealing to the asymmetry of good and evil, and quoting this ancient principle, in an ethical context in the not too distant past, so it may well have some contemporary appeal. Taking "perfection" in this familiar way, then, there is some justification for holding that "limited perfection" is generalisable; and if we have some faith in the doctrine of the transcendentals and their convertibility with existence, we may hold that this applies to the more general sense of perfection which St Thomas is employing here.
What is not at all clear is, as has been said, that whatever displays this feature X requires an explanation in terms of a relation to something else, let alone that it requires an explanation in terms of a relation to something of unlimited perfection. St Thomas seems to allege that the existence of a more and a less requires an explanation in terms of a relation to a most.
"But Ďmoreí and Ďlessí so-and-so are said of various things in so far as they approach, in their different ways, that which is most so-and-so, as that which is hotter is that which is closest to that which is hottest.
There is, then, something which is most true, and best, and most noble, and which therefore most exists: for those things which are most true are most existent, as it says in the second book of the Metaphysics.
That which is said to be greatest in any kind causes everything of that kind, as for example fire, which is the hottest thing, is the cause of all hot things, as it says in the same book."
There are some things which can be said. The existence of a more and a less does indeed require the existence of a de facto most: if all of the male lecturers of Glasgow University are more or less good-looking, then there will be one (allegedly the former Dean of Arts) who is the most good-looking. But this does not help us much: the Dean of Arts, though a fine figure of a man, has no chance next to Daniel Day-Lewis. His de facto relative highest beauty falls very far short even of a more widely extended relative beauty, let alone absolute beauty. In any case, the same point can be made with regard to defects as well as perfections. Lecturers in Glasgow are relatively ugly, and while it would be invidious to name names, there is no doubt that there is one who is the ugliest of the lot. This existence of a de facto most, which is required by the existence of a more and a less, will not get us where we want to go: particularly as I can see no reason whatsoever why the existence of the de facto most should cause or explain the existence of the more and the less.
One might try to claim that the existence of a more and a less requires a notion of the most, but I find this doubtful. And again, it is hard to see how the existence of an idea of the most can explain the real existence of the more and the less. Indeed, it is hard to see how the existence of any kind of idea can explain the real existence of anything at all. In any case, an argument like this is going to bring us only to the existence of an idea of God, which may be very interesting but was hardly in doubt from the beginning.
I am inclined to leave this argument as a mystery. But there is some slight illumination which I think may be cast on the problem by the original example of the group of Inuit. The phenomenon which needed to be explained in the case of the group of Inuit was their presence on a street corner in Glasgow. The presence of the group of Inuit, or of each member of the group, was the parallel to the existence of the world or of any part of it. One might query whether presence admits of degrees, and whether the existence of limited presence requires an explanation in terms of absolute presence.
Put like that, the story of the Inuit looks even more bizarre than the Fourth Way itself, but we can perhaps smooth off some of the rough edges. Presence may not admit of degrees, but presence on a street corner certainly does. If you have ever waited leaning against the wall on the street corner for someone who was meanwhile leaning on the wall just round the corner waiting for you, you will know what I mean. For a group of as many as five Inuit, the concept of standing on the street corner admits of degrees: unless the corner is of a very odd shape, or unless they are standing in a human tower on one anotherís shoulders, one will be nearer the corner than another.
Does this require explanation? Not really, since it is something that is so obvious. But it does require the existence of a street corner, for them to be nearer to or farther away from. The street corner is, I suppose, in some unlimited and perfect degree present at the street corner, since everything is in an unlimited and perfect degree present where it is. And in a sense it is the perfect and unlimited presence at the street corner of the street corner itself, which does something to explain the presence, to a greater or lesser extent, of the Inuit at the street corner. If there is no perfect and unlimited presence of the street corner, there will be no limited and varying degree of presence of the Inuit.
If this parallel represents in any way the argument St Thomas is trying to give us in the Fourth Way, then the Fourth Way is very different from the others. I do not know how to classify the kind of explanation of the world that it offers. But this fits fairly well with the text of the Fourth Way: "Therefore there is something that is the cause of the existence and the goodness and of all perfections in everything: and this, we say, is God." What kind of cause is being spoken of here is obscure. It is not a question of efficient, final, material, or even, so far as I can make out, formal cause. Equally well the presence of the street corner explains the presence of the Inuit in a quite different way from the story that they are a dance troupe due to perform Mayfest, or that Kadlu is signing for Thistle; that they are waiting for a bus or even that they have been transported there by a whirlwind, as in The Wizard of Oz. It is a strange argument, and the stranger the notion of explanation we claim is being used in it, the better chance we have of being right. Or perhaps I should say, the slightly less chance we have of being wrong. Good luck to the next person to approach the Fourth Way.
Go to Fifth Proof