The Problem of Truth

by Herbert Wildon Carr

A short time ago an orang-utang escaped from its cage in the Zoological Gardens under somewhat singular and very interesting circumstances. The cage was secured with meshed wire of great strength, judged sufficient to resist the direct impact of the most powerful of the carnivora; but the ape, by attention to the twisting of the plied wire, had by constant trying succeeded in loosening and finally in unwinding a large section. It escaped from its enclosure, and after doing considerable damage in the corridor, including the tearing out of a window frame, made its way into the grounds and took refuge in a tree, twisting the branches into a platform said to be similar to the constructions it makes in its native forests.

In taking this action as an illustration, I am not concerned with the question of what may be the distinction between action that is intelligent and action that is instinctive. If we take intelligence in a wide and general meaning, we may compare the intelligence shown by this ape with the intelligence shown by man in the highest processes of the mind. Psychologists would, I think, be unanimous in holding that in the mind of the ape there was no conception of freedom, no kind of mental image of unrestricted life and of a distinct means of attaining it, no clearly purposed end, the means of attaining which was what prompted the undoing of the wire, such as we should certainly suppose in the case of a man in a similar situation. It was the kind of intelligent action that psychologists denote by the description "trial and error." It seems to me, however, that this exactly fulfils the conditions that the pragmatist doctrine of the meaning of truth require. We see the intellect of the ape making true by finding out what works. We can suppose an entire absence of the idea of objective truth to which reality must conform, of truth unaffected by purpose. Here, then, we seem to have the pure type of truth in its simplest conditions, a practical activity using intelligence to discover what works. Is the difference between this practical activity and the higher mental activities as we employ them in the abstract sciences one of degree of complexity only, or is it different in kind?

Let us consider now, as an illustration of the method of the abstract sciences, the well-known case of the discovery of the planet Neptune. This planet was discovered by calculation and deduction, and was only seen when its position had been so accurately determined that the astronomers who searched for it knew exactly the point of the heavens to which to direct their telescopes. The calculation was one of extraordinary intricacy, and was made independently by two mathematicians, Adams of Cambridge and Leverrier of Paris, between the years 1843 and 1846. Each communicated his result independently—Adams to the astronomer Challis, the Director of the Cambridge Observatory, and Leverrier to Dr. Galle of the Berlin Observatory. Within six weeks of one another and entirely unknown to one another, in August and September 1846, each of these astronomers observed the planet where he had been told to look for it. This is one of the romances of modern science. It is not the discovery but the method that led to it which may throw light on our problem of the nature of truth.

At first sight this seems exactly to accord with and even to illustrate the pragmatist theory, that truth is what works. The investigation is prompted by the discrepancies between the actual and the calculated positions of Uranus, the outermost planet, as it was then supposed, of the system. This revealed a need, and this need was met by the practical postulate of the existence of another planet as yet unseen. The hypothesis was found to work even before the actual observation put the final seal of actuality on the discovery. What else but the practical consequences of the truth claim in the form of the hypothesis of an undiscovered planet were ever in question? Yes, we reply, but the actual method adopted, and the knowledge sought for by the method, are precisely of the kind that pragmatism rejects as "useless" knowledge. Why were not the observed movements of Uranus accepted as what they were? Why was it felt that they must be other than they were seen to be unless there was another planet? The need lay in the idea of system. It was inconsistent with the system then believed complete, and the need was to find the complete system in which it would harmonise. The truth that was sought for was a harmonious individual whole, and the method employed precisely that which the Absolutist theory of reality employs. There is observed a discrepancy, an inconsistency, a contradiction within the whole conceived as a system. This negation is treated as a defect, is calculated and accurately determined, and is then positively affirmed of the reality. Now, what is distinctive in this method is that reality is conceived as a complete system. If the felt defect in this system cannot be made good by direct discovery, its place is supplied by a fiction, using the term in its etymological meaning to express something made and not in its derived meaning to express something found false. This intellectual process of construction is purely logical; no psychological element in the sense of the will to believe enters into it or colours it in any way.

This is not an isolated instance, it illustrates the method of science in all theorising. An even more striking illustration than that we have just given is the case of the hypothesis of the luminiferous æther—a supposed existence, a fiction, that has served a useful, even an indispensable service in the history of modern physics. To many physicists, even to Lord Kelvin, the hypothesis seemed so surely established that its nonexistence hardly seemed thinkable, yet all the experiments designed to detect its presence have been uniformly negative in result, and it now seems not even necessary as a hypothesis, and likely to disappear. The æther was not only not discovered, it was not even suspected to exist, as in the case of the unknown planet Neptune—it was logically constructed. It was required to support the theory of the undulatory nature of light and to fulfil the possibility of light propagation in space. It was therefore a postulate, called forth by a need—so far we may adopt the pragmatist account. But what was the nature of the need, and what was the method by which the postulate was called forth? It is in answering this question that the pragmatist criterion fails. The need was intellectual in the purely logical meaning of the term, and it was met by a purely logical construction. The need was a practical human need only in so far as the intellect working by logical process is a human endowment but not in any personal sense such as is conveyed by the term psychological. Willingness or unwillingness to believe, desire, aversion, interest were all irrelevant. Given the intellect, the logical necessity was the only need that called forth by logical process the "truth-claiming" hypothesis of the æther. But even so, the pragmatist will urge, is its truth anything else but its usefulness as shown in the practical consequences of believing it? Was it not true while it was useful, and is it not only now false, if it is false, if it is actually discovered not to be useful? The reply is that no mathematician or physicist would recognise the possibility of working with a conception of truth that simply identified truth with utility, and for this reason that he can only conceive reality as a system whose truth is symbolised in an equation. It is the system that determines and characterises the postulate, and not the postulate advanced at a venture, tried and verified, that constitutes the system. The mathematician begins by placing symbols to represent the unknown factors in his equation, and proceeds by means of his known factors to determine their value. The æther is at first a pure fiction constructed to supply an unknown existence recognised as a defect. Its truth cannot mean that it works for it cannot but work, having been constructed purely for that purpose. Its truth means that it corresponds to some actual existence at present unknown. To prove its truth the physicist does not appeal to its value as a hypothesis, but devises experiments by which, if it does exist, its existence will be demonstrated. In this actual case the experiments have had a uniformly negative result, and therefore the truth of the hypothesis is made doubtful or denied. The hypothesis continues to work as well as it ever did, and physicists will probably long continue to use it, but it has failed to establish its truth claim. The result is the modern Principle of Relativity, which, as we have already said, has produced a revolution in modern physics. The abolition of the æther would have been impossible if the physicist had been content with the utility of his hypothesis and had not experimented to prove its truth. The relation between truth and utility is thus proved to be that it is useful to know what is true.

These two illustrations of scientific method—namely, the discovery of Neptune and the negative discovery that the æther is non-existent—make it evident that verification is the intellectual process not of making true, but of finding true. We can, indeed, distinguish quite clearly the two processes. The first process, that of making true, is the constructing of the fiction by which we complete an incomplete system, and the second is the testing of that fiction to see if it corresponds to anything actually existing. No kind of intellectual activity will make an idea true, and conversely we may say that were truth only a utility, then knowledge instead of being systematic would be chaotic. Existence has its roots in reality, not in knowledge. Reality does not depend on truth. Truth is the intellectual apprehension of reality.

If the pragmatist objects that in this argument I have throughout supposed him to be urging the narrow meaning of utility, namely, that it is usefulness in the strictly practical sense, whereas he intends it in the widest possible meaning—a meaning that includes theoretical usefulness—then the trouble is a different one; it is to know how and where the pragmatist stops short of the coherence theory of truth, and wherein his method differs from that of the idealist.

This brings me to the consideration of another theory in which the concept of utility plays a large, indeed a predominant part. This is the theory of the relation of knowledge to life that is given to us in the philosophy of Bergson. I have in one of the volumes of this series given an account of this philosophy; I am here only dealing with its relation to this special problem of the nature of truth. It has been claimed that this philosophy is only a form of pragmatism, but it is not a theory of truth, and it has this essential difference from pragmatism that it is the intellect and not truth that is a utility. Before we consider the question that it gives rise to in regard to truth, let us first examine the theory of the intellect, and the nature of its utility. The intellect is a mode of activity, an endowment acquired in the course of evolution, and which has been retained and perfected because of its utility. This does not mean that the intellect directs us to what is useful and inhibits us from courses fatal to life, neither does it mean that it gives us any power to make true what is not already true, it means that the power to acquire knowledge is useful. There is a contrast in our own existence between our life and our intellect.

To understand the way in which the intellect serves the living creature endowed with it, we need only regard it from the standpoint of ordinary experience. We know in ourselves that our life is wider than our intellect, and that our intellect serves the activity of our life. The common expressions we employ, such as using our wits, taking an intelligent interest, trying to think, all imply a utility distinct from the intellect. So viewed, our life appears as an active principle within us, maintaining our organism in its relations, active and passive, and reactive to the reality outside and independent of it. Our intellect also seems both active and passive. It receives the influences that stream in upon us from the reality around us, it apprehends and interprets them, and works out the lines of our possible action in regard to them. The influences that flow in upon us from the outside world are already selected before our intellect apprehends them, for they flow in by the avenues of our senses, and the senses are natural instruments of selection. If we picture these influences as vibrations, then we may say that a certain group of vibrations of a very rapid frequency are selected by the eye and give rise to vision, that another group of very much lower frequency are selected by the ear and give the sensation of sound, and other groups are selected by taste, smell, and touch. Many groups are known indirectly by means of artificial instruments, and all the infinite series that unite these groups of the actually experienced vibrations escape our apprehension altogether—we have no means of selecting them. But all these sense data, as we may call them, come to us without exertion or activity on our part; it is the intellect which gives them meaning, which interprets them, which makes them the apprehension or awareness of objects or things. And the active part that the intellect plays is also a process of selection. This is evident if we reflect upon the universal form which our intellectual activity takes, namely, attention. It is in the act of attention that we are conscious of mental activity, and attention is essentially selection—the selection of an interest. Besides the natural selection that is effected by our senses and the conscious selection that is manifest in attention, there is also a more or less arbitrary selection that our intellect performs in marking out the lines of our practical interest and possible action. In this work of selection the intellect makes the world conform to the necessities of our action.

So far we have looked at our intellectual endowment from the standpoint of ordinary common-sense experience. Let us now consider the philosophical theory based on this view, which explains the nature of knowledge by showing its purpose. The intellect not only selects, but in selecting transforms the reality. It presents us with knowledge that indeed corresponds with reality, for it is essentially a view of reality, but also in selecting it marks out divisions, and gives to reality a form that is determined by practical interest. The same reality is different to different individuals and to different species according to their practical interests. The practical end which the human intellect serves is to present us with a field for our life activity. This is the real world for us, as we know it, real objects in a real space. Had we no other way of knowing but that of our intellect we should not know the life which is active within us as it is really lived, we should be as those who, standing outside, watch a movement, and not as those who are carried along in the movement and experience it from within. In life and intellect we have the counterpart of reality and appearance. Life is not something that changes; it is the change of which the something is the appearance. Life is the reality of which all things, as we understand them, are the appearances, and on account of which they appear. The solid things in space and time are not in reality what they appear; they are views of the reality. The intellect guided by our practical interest presents reality under this form of solid spatial things. Clearly, then, if this view be true, the whole world, as it is presented to us and thought of by us, is an illusion. Our science is not unreal, but it is a transformed reality. The illusions may be useful, may, indeed, be necessary and indispensable, but nevertheless it is illusion.