they see smoke in just the same way as it trained them to expect that all swans would be white (until they saw a black one) or that water would always boil at 212° (until someone tried a picnic on a mountain). Such expectations are not inferences and need not be true. The assumption that things which have been conjoined in the past will always be conjoined in the future is the guiding principle not of rational but of animal behaviour. Reason comes in precisely when you make the inference ‘Since always conjoined, therefore probably connected’ and go on to attempt the discovery of the connection. When you have discovered what smoke is you may then be able to replace the mere expectation of fire by a genuine inference. Till this is done reason recognises the expectation as a mere expectation. Where this does not need to be done—that is, where the inference depends on an axiom—we do not appeal to past experience at all. My belief that things which are equal to the same thing are equal to one another is not at all based on the fact that I have never caught them behaving otherwise. I see that it ‘must’ be so. That some people nowadays call axioms tautologies seems to me irrelevant. It is by means of such ‘tautologies’ that we advance from knowing less to knowing more. And to call them tautologies is another way of saying that they are completely and certainly known. To see fully that A implies B does (once you have seen it) involve the admission that the assertion of A and the assertion of B are at bottom in the same assertion. The degree to which any true proportion is a tautology depends on the degree of your insight into it. 9 × 7 = 63 is a tautology to the perfect arithmetician, but not to the child learning its tables nor to the primitive calculator who reached it, perhaps, by adding seven nines together. If Nature is a totally interlocked system, then every true statement about her (e.g. there was a hot summer in 1959) would be a tautology to an intelligence that could grasp that system in its entirety. ‘God is love’ may be a tautology to the seraphim; not to men.
‘But’, it will be said, ‘it is incontestable that we do in fact reach truths by inferences’. Certainly. The Naturalist and I both admit this. We could not discuss anything unless we did. The difference I am submitting is that he gives, and I do not, a history of the evolution of reason which is inconsistent with the claims that he and I both have to make for inference as we actually practise it. For his history is, and from the nature of the case can only be, an account, in Cause and Effect terms, of how people came to think the way they do. And this of course leaves in the air the quite different question of how they could possibly be justified in so thinking. This imposes on him the very embarrassing task of trying to show how the evolutionary product which he has described could also be a power of ‘seeing’ truths.
But the very attempt is absurd. This is best seen if we consider the humblest and almost the most despairing form in which it could be made. The Naturalist might say, ‘Well, perhaps we cannot exactly see—not yet—how natural selection would turn sub-rational mental behaviour into inferences that reach truth. But we are certain that this in fact has happened. For natural selection is bound to preserve and increase useful behaviour. And we also find that our habits of inference are in fact useful. And if they are useful they must reach truth’. But notice what we are doing. Inference itself is on trial: that is, the Naturalist has given an account of what we thought to be our inferences which suggests that they are not real insights at all. We, and he, want to be reassured. And the reassurance turns out to be one more inference (if useful, then true)—as if this inference were not, once we accept his evolutionary picture, under the same suspicion as all the rest. If the value of our reasoning is in doubt, you cannot try to establish it by reasoning. If, as I said above, a proof that there are no proofs is nonsensical, so is a proof that there are proofs. Reason is our starting point. There can be no question either of attacking or defending it. If by treating it as a mere phenomenon you put yourself outside it, there is then no way, except by begging the question, of getting inside again.
A still humbler position remains. You may, if you like, give up all claim to truth. You may say simply ‘Our way of thinking is useful’—without adding, even under your breath, ‘and therefore true’. It enables us to set a bone and build a bridge and make a Sputnik. And that is good enough. The old, high pretensions of reason must be given up. It is a behaviour evolved entirely as an aid to practice. That is why, when we use it simply for practice, we get along pretty well; but when we fly off into speculation and try to get general views of ‘reality’ we end in the endless, useless, and probably merely verbal, disputes of the philosopher. We will be humbler in future. Goodbye to all that. No more theology, no more ontology, no more metaphysics …
But then, equally, no more Naturalism. For of course Naturalism is a prime specimen of that towering speculation, discovered from practice and going far beyond experience, which is now being condemned. Nature is not an object that can be presented either to the senses or the imagination. It can be reached only by the most remote inferences. Or not reached, merely approached. It is the hoped for, the assumed, unification in a single interlocked system of all the things inferred from our scientific experiments. More than that, the Naturalist, not content to assert this, goes on to the sweeping negative assertion. ‘There is nothing except this’—an assertion surely, as remote from practice, experience, and any conceivable verification as has ever been made since men began to use their reason speculatively. Yet on the present view, the very first step into such a use was an abuse, the perversion of a faculty merely practical, and the source of all chimeras.
On these terms the Theist’s position must be a chimera nearly as outrageous as the Naturalist’s. (Nearly, not quite; it abstains from the crowning audacity of a huge negative). But the Theist need not, and does not, grant these terms. He is not committed to the view that reason is a comparatively recent development moulded by a process of selection which can select only the biologically useful. For him, reason—the reason of God—is older than Nature, and from it the orderliness of Nature, which alone enables us to know her, is derived. For him, the human mind in the act of knowing is illuminated by the Divine reason. It is set free, in the measure required, from the huge nexus of non-rational causation; free from this to be determined by the truth known. And the preliminary processes within Nature which led up to this liberation, if there were any, were designed to do so.
To call the act of knowing—the act, not of remembering that something was so in the past, but of ‘seeing’ that it must be so always and in any possible world—to call this act ‘supernatural’, is some violence to our ordinary linguistic usage. But of course we do not mean by this that it is spooky, or sensational, or even (in any religious sense) ‘spiritual’. We mean only that it ‘won’t fit in’; that such an act, to be what it claims to be—and if it is not, all our thinking is discredited—cannot be merely the exhibition at a particular place and time of that total, and largely mindless, system of events called ‘Nature’. It must break sufficiently free from that universal chain in order to be determined by what it knows.
It is of some importance here to make sure that, if vaguely spatial imagery intrudes (and in many minds it certainly will), it should not be of the wrong kind. We had better not envisage our acts of reason as something ‘above’ or ‘behind’ or ‘beyond’ Nature. Rather ‘this side of Nature’—if you must picture spatially, picture them between us and her. It is by inferences that we build up the idea of Nature at all. Reason is given before Nature and on reason our concept of Nature depends. Our acts of inference are prior to our picture of Nature almost as the telephone is prior to the friend’s voice we hear by it. When we try to fit these acts into the picture of Nature we fail. The item which we put into that picture and label ‘Reason’ always turns out to be somehow different from the reason we ourselves are enjoying and exercising while we put it in. The description we have to give of thought as an evolutionary phenomenon always makes a tacit exception in favour of the thinking which we ourselves perform at that moment. For the one can only, like any other particular feat, exhibit, at particular moments in particular consciousnesses, the general and for the most part non-rational working of the whole interlocked system. The other, our present act, claims and must claim, to be an act of insight, a knowledge sufficiently free from non-rational causation to be determined (positively) only by the truth it knows. But the imagined thinking which we put into the picture depends—because our whole idea of Nature depends—on the thinking we are actually
