§ 1

Such in outline was the argument which I developed more at length in the Gifford Lectures of 1914. That it does nothing towards establishing a metaphysical system is plain enough; and this not merely through defects of exposition, though these I doubt not exist in plenty, but because the argument itself has a different and much less ambitious aim. It neither is, nor pretends to be, more than an argumentum ad hominem. It is an individualist appeal to the sentiments and beliefs of individuals. To every reader or hearer it says in effect that, unless he assumes the reality of a universe which is spiritually guided, the values, which in his eyes are supreme, must lessen and fade. It is not, for example, in a world where love and beauty are treated as the transitory and ineffectual accidents of material evolution that they will retain their values undimmed and undiminished. Would he avoid this catastrophe he must therefore modify the pure teaching of naturalism by infusing into his theory of the universe the ethical and aesthetical purpose of which naturalism can find no trace.

Now there are many persons to whom this line of thought, even when limited to the first two values, makes effective appeal. They attach no great importance to naturalistic negations; they are not seriously perturbed by the difficulties of optimism; and when they survey the splendours of nature or sound the depths of love, they instinctively shrink from regarding these as no more than undesigned effects of a soulless machine.

But there are others of a different temper, to whom the appeal, however moving, if limited to the case of love and beauty, seems insufficient for the task it is asked to perform. They regard it as a device for protecting beliefs of emotion—lofty emotion, no doubt, but still emotion—against the corroding consequences of scientific discovery. The choice presented to them they deem to be a choice between the true and the attractive. “Truth (they say) has a claim on our allegiance, supreme and indefeasible. Though knowledge in its remorseless progress tumbles all other ideals in the dust, still if it be knowledge, it must be reverently followed and patiently obeyed. We rate love and beauty no less highly than our neighbours. But if you tell us that their values can only be maintained by ignoring conclusions to which science points the way, our choice is made. Between these alternatives we shall never hesitate.”

It would be wrong to say that to persons in this mood the argument makes no appeal. It appeals, though ineffectually. But there is a third class to whom it makes no appeal at all. It is not every man who troubles himself about the “emotional” values; and for those who do not, there can be no struggle between opposing ideals. So far as they are concerned the argumentum ad hominem is but an empty menace, involving in the case of dissent the surrender of nothing which they would seriously miss.

§ 2

Now these three examples show clearly how and why the argumentum ad hominem, if limited to the two first values, loses something of its effect. It touches a smaller audience. It lacks universality. It leaves unconvinced, though not perhaps unmoved, many of those who think that “positive” knowledge stands on a wholly different and far surer basis than beliefs of emotion; it leaves quite unmoved, as well as unconvinced, those to whom beliefs of emotion mean little or nothing.

Nor can this defect be removed except by removing its cause; and its cause can only be removed by showing that the values of knowledge are as dependent on a spiritual outlook as the values of beauty or of love. Were this task accomplished the desired universality would seemingly be attained. For in respect of common sense and science, all men should be interested, for all men are believers. The personal appeal, if valid at all, is valid for everyone. It may be answered, it may be ignored. But no man can treat it as irrelevant; for every deliberate action of his waking life is guided by beliefs which bring him within its scope.

§ 3

While the argument from the third of the great values is thus in a privileged position, I do not deny that the universality of its appeal is rather theoretical than practical. It is obviously neither possible nor desirable that the human race should sit solemnly down and consider how the truth—or at least the truthwardness—of its familiar beliefs can best be explained. Suitable though such a question may be to the situation of thinking beings like us, domiciled in a world like ours, few will be disposed to ask it, and still fewer will take the pains to understand any answer to it which is thought to be tainted with “metaphysic.” Many persons, indeed, are interested in Theism, but not many are prepared to approach its consideration through the esoteric teaching of the schools. Outside Scotland, indeed, philosophers do not, I fear, stand high in popular esteem. They are supposed to question what nobody doubts, and to explain what everybody understands. Obscure thoughts couched in uncouth language, subtle argumentations which convince no one and lead nowhere, constitute (so it is believed) their principal stock-in-trade; and though traditions of culture may require them to be treated with some measure of respect, this is by no means inconsistent with the most perfect neglect of anything they may have to say. Before such an audience as this, philosophers (I am sure) require no defence. But it may perhaps be admitted that in face of prejudices like these (no doubt more often felt than expressed) it may be worth while to hazard some observations on the relation of philosophy to the general argument on which we are engaged.

§ 4

I have disowned any intention of propounding a system of my own; I have no inclination to advocate the systems of other people; and I am anxious, for reasons already indicated, to express my views, when they trespass on subjects usually reserved for philosophers, in language as little technical as possible. But how, it may be asked, is such an attitude to be justified? If it be granted that the problems dealt with have a philosophic side, why (it may be said) in dealing with them should we thus keep philosophy at arm's length? Those who discourse about the stars consult astronomers; those who are troubled about their health consult physicians. This is not, I suppose, because they cherish the illusion that in these or any other subjects experts are infallible, but because they think that whether the advice of experts be good or bad, it is at least the best that can be obtained. Why not treat philosophers as we treat astronomers and doctors? No one suggests that they are less able or less honest; why, then, act as if they were less competent?

This contention, however, plausible as it may seem, is based on a misconception. Philosophy is neither an art like medicine, nor a science like astronomy, nor a court of general appeal which the sciences are prepared to acknowledge. What, then, is it? And who are philosophers?

Perhaps we might reply that every man who consciously theorises about the universe at large may claim to be a philosopher; and that if his theories, as recorded by himself or his disciples, are fortunate enough to impress the world, they are entitled to count as a contribution to philosophy.1 In this way, there has grown up a body or “canon” of the writings which are deemed to enshrine the philosophic thought which, from age to age, has seemed most worthy the attention of mankind. Its contents, I need hardly say, show no unity of purpose or fixity of outline. It has been written in many periods and from many points of view. It pretends to no sort of consistency. Yet, in spite of all, it shows a singular vitality, which seems yet more remarkable when we compare it with what has occurred in the parallel case of science. For the teaching of the great philosophers, though it appeals only to the few, seems rarely to be wholly superseded. It is never completely neglected, perhaps because it is never completely absorbed. Not so with the great discoverers. Men still consult Plato and Aristotle, Hume and Kant. But who goes for astronomy to Copernicus, or for chemistry to Boyle? These illustrious names stand in no peril of oblivion. They are imperishable milestones on the highway of knowledge. But new discoveries and new generalisations add so greatly to what they truly taught, and sweep their errors so rapidly into forgetfulness, that, unless by example, they have little now to teach us. In science, the last things are always the best, and the newest treatise is commonly the most instructive.

§ 5

It would be almost as hazardous to make a similar statement about philosophy as to make it about literature—a fact which at first sight is sufficiently surprising. We might have supposed that out of the age-long disputes recorded in histories of philosophy there would gradually have emerged a body of doctrine, generally accepted, and well fitted to serve as a base of operations from which new adventures might be securely attempted. In science this has happened on an immense scale; but few will allege that it has happened in philosophy. The most, perhaps, that we can say is that some errors have been finally refuted, that some venerable theories have been disengaged from unessential blemishes; and that over some alluring paths “No thoroughfare” has been writ so large that even the boldest explorer must pause and turn.

This seems a poor result of six and twenty centuries of speculation; and so it certainly is, if we insist on applying to philosophy the standard we rightly apply to science. But this would be unjust. For it may be urged that if philosophy resembles science in that it strives to further systematic knowledge, it resembles literature in that it expresses not merely one aspect of the age which produced it, but the particular quality of individual genius. The teacher has value beyond his teaching. His personality retains its power when his arguments have sunk into senility. And thus it comes about that students will glean, and glean again, over philosophic fields long since harvested by their forerunners—seeking, and perhaps finding, inspiration from systems, not one characteristic doctrine of which they are prepared to accept in the form designed by its original author.

§ 6

These peculiarities make it very hard to measure the exact importance of the part that has been played by philosophy in the progress of mankind. Systems rise and fall. They have their day. As with art, as with letters, as with dress, favour largely goes by fashion: and for reasons not easy to disentangle, now one school of thought predominates, now another. But be they on the crest of the wave or in the trough, what influence have any of them exercised on the ordinary beliefs of ordinary men? When they supply arguments that can be turned to account in some controversy of general interest, they are, of course, loudly, if not intelligently, welcomed by those who claim them as allies—for in this respect the battle-fields of philosophy do not differ from those of politics or war. But how far have they moulded and modified the general character of civilised thought? How far have they controlled general opinion? How far have they merely reflected it? How far have they been beside it or beyond it?

Philosophers, who differ about most things, differ even about the importance of philosophy. My own view (which I express with much diffidence) is that while on religion and ethics the speculations embodied in the philosophical canon have had an important influence, on the familiar beliefs which supply the raw material of these lectures, their effect has been negligible. Consider for a moment the case of science. Is there any evidence that they have modified in the smallest degree our beliefs about the world of Nature? Of some Greek speculations it is hard to say whether at their birth they should have been registered as science or as philosophy, for in fact they were both. But modern science, as far as I can see, owes philosophy nothing.2 It is alleged that the illegitimate use of traditional philosophic categories, e.g. “substance” and “essence,” the authority of such maxims as “cause and effect are equal” or “the effect ceases with the cessation of its cause,” have, in some cases, retarded progress. But I am not sure that it is true, and if true it is little to the purpose. As late as Hegel, indeed, who, at an ill-chosen moment, determined the number of the planets by the laws of thought, philosophy has occasionally thrust itself into the domain of science; but such raids were never effective, have long been out of favour, and are never likely to be repeated. Some philosophers, like Aristotle in the ancient world, Descartes and Leibnitz in the modern, have greatly furthered scientific progress; but they did not do it as philosophers but as naturalists, mathematicians, and physicists. Bacon, the prophet of experimental and applied science, did much by his genius and his eloquence to put these subjects in a just perspective; but to scientific knowledge he added little. Philosophers like Hume have acquired fame by making critical attacks on the foundations of science; other philosophers, like Kant, have acquired fame by devising critical replies. But science—profoundly indifferent both to the attack and the defence—has throughout remained serenely unconscious that its fate, as judged by speculative reason, was hanging doubtfully in the balance!

This example is, I think, instructive. Hume's scepticism was famous in its day—and indeed is famous still. But by the unphilosophic public it was, and is, supposed to be level led mainly against religion. As a matter of fact, this is not so. Science was theoretically in even greater peril than theology. But while theologians well knew that Hume had made use of arguments which it was their business to answer, it never occurred (so far as I know) to any men of science that their entrenchments also were under fire, and that it behoved them to strengthen their defences. They had a well-grounded confidence that, however open to attack science might seem to those who were playing a dialectical “war-game,” in the world of practice it was certainly impregnable.

So it has come about that while philosophy has concerned itself more and more with the groundwork of scientific knowledge, science has neither returned the compliment nor followed the example. It takes little interest in its own first principles, and pays little attention to those who do. I am far from saying that its procedure is wrong; but I submit that it is interesting, and not without a moral to which I shall refer before the present course of lectures is brought to an end.

§ 7

Moreover, it must be observed that this indifference to philosophy on the part of science, though not often expressed in terms, is sincere and thorough. There is a species of indifference of quite another type, which is neither so reticent nor so genuine. A man who has glanced without comprehension at an article on electromagnetic theory may throw it aside exclaiming that this is a subject about which he neither knows anything nor wants to know anything. But he does not really mean by this that the article deals with matters which in no way concern him. On the contrary, he is probably well aware of their importance. What he means is that in a world where there is minute subdivision of labour and great diversity of gifts, it cannot be his particular business to master a branch of abstruse learning, for which he possesses neither aptitude nor inclination.

But unless I be greatly mistaken this is not in the least the attitude towards philosophic speculation adopted by most men of science. If, as sometimes happens, one of them is interested also in philosophy, it is not because he thinks that his philosophy is going to throw light on his science, but because he is concerned about problems with which philosophy does and science does not make some attempt to deal. If by mischance the two lines of investigation clashed, it would never occur to him that his science ought to give way, although in the order of logic his philosophy must surely be the more fundamental. This attitude may be right or wrong; but at least it is an indication that while science means much to philosophy, philosophy means little to science; and we may certainly add that if it means little to science, it means still less to ordinary men in the conduct of their ordinary affairs.

In these circumstances we need feel no surprise that while philosophy is, as we are all aware, somewhat prone to patronising religion, it very meekly takes its orders from science. I do not, of course, mean that science prescribes its methods, or controls its conclusions. I merely mean that when science speaks with a united voice, philosophy never ventures to contradict it. We live in a scientific age, and this attitude may seem as natural now as it would have seemed unnatural a few centuries ago. But whether natural or unnatural, it is surely very paradoxical. We have on the one side science uncritically based on uncriticised common sense, but triumphant, successful, united. On the other, we have philosophy profoundly divided against itself, conscious of a great mission, yet unable to agree how best to accomplish it. On the one side, we have science, barely aware that philosophy exists, and not aware at all that its conclusions have any scientific interest. On the other, we have philosophy, respectfully accepting all scientific conclusions, though sometimes not insensible to unsolved difficulties which science calmly ignores, or brushes contemptuously away. On the one side, we have science de facto lord of its own great province of belief; and on the other, philosophy de jure judge of all the knowable, striving to make good the title of its all-powerful vassal, but so far striving in vain!

If any think this picture overcharged, either as regards the subservience of philosophy to science in respect of its conclusions, or the logical dependence of science on philosophy in respect of its premises, or the failure of philosophers to agree on any theory of knowledge, or the total indifference of science as to whether they agree or not, let him compare the histories respectively of philosophy and science from the seventeenth century to the twentieth, and I venture to think that he will alter his opinion.

§ 8

These observations, however incomplete, may sufficiently explain why so large a proportion of educated persons treat philosophy as negligible. They derive their world view, when they have one, either from current science or current theology,3 or both. The philosophic “canon,” whether ancient or modern, to them means nothing, nor do they connect their familiar beliefs with any of the metaphysical systems which have from time to time found favour in the schools. Our position in these lectures is somewhat different. Like the rest of the world we accept the general body of familiar beliefs—scientific and other—but they constitute the beginning of our investigations, not the end. Our journey lies still before us, and in the course of it we shall sometimes have to touch on problems which the wisdom or the idleness of mankind has gladly left to philosophy. I regret the necessity; for I am well aware that I thus lay myself open to a double criticism. Philosophers will complain that I have engaged in controversies about which I should either have said nothing or have said more, while those who think all philosophic controversy futile or unintelligible will resent the attempt to force them into unaccustomed modes of thought. It is these last whom I most desire to reassure. I do not deny that the road which lies before us may appear somewhat less easy than that which we have already traversed. But this is not because it leads us far from common things into the heights of metaphysical speculation, but rather because even the foothills of philosophy may call for exertions of a kind which, though not intrinsically difficult, are a little unusual, and perhaps for that reason somewhat unattractive. I am, however, bold enough to hope that even the least accustomed traveller will, on a fair trial, find his journey neither so rough nor so tedious as he may be inclined to fear.

• 1.

  This is, of course, a very rough explanation of a word which is very loosely used. In particular the dividing line between philosophy and theology (where there is one) may be endlessly disputed. Let me add that throughout these lectures I have primarily in view only Western speculations and Western modes of thought.

• 2.

  See my observations on the atomic theory in “Theism and Humanism”, p. 220.

• 3.

  I do not, of course, mean to suggest that theology has been uninfluenced by philosophy. See above.