(2) Again, we may with effect present our argument in a negative form. Try, we may say, to think of the utterly unreal, and see how you will have to conceive it. Can you think of sheer unreality otherwise than as that of which no mind is ever aware, of which no purpose has ever to take account as a condition of its fulfilment? But to think of it thus is to attribute to it, as its definition, precisely that independence in which the realist finds the mark of ultimate reality. And if “independence” constitutes unreality, presence to and union with experience must be what constitutes reality.
Yet, however fatal this line of argument may be to the principle of the realistic contention, we ought not to be satisfied with such a mere general refutation. We must try to see what is the element of truth in the realistic views to which they owe the plausibility they have always possessed for minds of a certain type. In Philosophy we are never really rid of an error until we have learned how it arises and what modicum of truth it contains.
(1) Agnostic Realism. We may begin with Agnosticism, with which we ought now to have no serious difficulty. Agnostic Realism, as we have seen, is in principle a doubly self-contradictory theory. For it combines in one breath the irreconcilable declarations that the reality of things is unknowable and that it knows it to be so.[[45]] Further, as we have just said, it makes alleged contradictions which only exist in and for experience, its sole ground for affirming that something, of which we can only specify that it is outside all experience, transcends cognition. To have grasped these two points is to have disposed of Agnosticism as a metaphysical theory.
Yet with all its defects Agnosticism still enshrines one piece of truth which the metaphysician is peculiarly prone to forget. Of all men the metaphysician, just because his special interest is to know something final and certain about Reality, is the most apt to exaggerate the amount of his certain knowledge. It is well to be reminded that the certainty with which we may say that Reality is experience is compatible with a very imperfect and limited theoretical insight into experience itself. In actual life this is a far from unfamiliar fact; the literature of common sense is full of observations to the effect that we never really know our own hearts, that the most difficult task of the sage is to understand himself, and so forth,—complaints which all turn on the point that even our own limited direct experience of our own meanings and purposes goes far beyond what we can at any moment express in the form of reflective knowledge. Yet it is easy, when we come to deal in Metaphysics with the nature of ultimate Reality, to forget this, and to suppose that the certainty with which we can say that the ultimately Real is an experience justifies us in wholesale dogmatising about the special character of that experience. As a protest against such exaggerated estimates of the extent of our theoretical knowledge of the nature of Reality, Agnosticism thus contains a germ of genuine and important truth, and arises from a justifiable reaction against the undue emphasising of the merely intellectual side of our experience, of which we have already seen, and shall hereafter still more fully see, ground to complain as a besetting weakness of the metaphysically minded.
(2) Dogmatic Realism, that is, Realism with admittedly knowable independent “reals,” is a much more workable doctrine, and in one of its forms, that of the so-called “naïve realism” which supposes the world of experienced things with all its perceived qualities to exist independently of any relation to an experiencing subject in precisely the same form in which we experience it, fairly represents the ordinary views of unphilosophical “common-sense” men. Nothing seems more obvious to “common sense” than that my perception of a thing does not bring it out of nothing into existence, and again does not create for it new qualities which it had not before. It is because the thing is already there, and has already such and such a nature, says “common sense,” that I perceive it as I do. Therefore the whole world of perceived things must exist independently in the same form in which they are perceived, as a condition of my perception of them.
When this view comes to be worked out as a philosophical theory, it usually undergoes some transformation. The fact of illusion, and the experimentally ascertained subjective differences between individual percipients,[[46]] or between different states of the same percipient, make it hard for the realist who wishes to be scientific to maintain that all the perceived qualities of experienced things are equally independent of the experiencing subject. Reflection usually substitutes for the “naïve” realism of everyday life, a theory of “scientific” realism according to which the existence and some of the known properties of the experienced world are independent of the experiencing subject, while others are regarded as mere secondary effects arising from the action of an independent reality on the subject’s consciousness. With the further differences between the various types of scientific realism, according to the special properties which are held to belong to things independently of the percipient subject, we are not at present concerned.[[47]]
It is, of course, clear that our general argument against the existence of any reality except as in an experience tells just as much against “naïve” realism and its more reflective outgrowth “scientific” realism as against Agnosticism. But the very plausibility and wide diffusion of realistic views of this type make it all the more necessary to reinforce our contention by showing what the truth Realism contains is, and just where it diverges from truth into fallacy. Nor is it specially difficult to do this. The important elements of truth contained in Realism seem to be in the main two. (i) It is certain that a thing may be real without being consciously present as a distinguishable aspect in my experience. Things do not begin to exist when I begin to be aware of them, or cease to exist when I cease to be aware of them. And again, the fact that I make mistakes and am subject to illusion shows that the qualities of things are not necessarily in reality what I take them to be. (2) Further, as is shown by the fact of my imperfect understanding of my own feelings and purposes, something may actually be an integral part of my own life as an experiencing subject without my clearly and consciously recognising it as such when I reflect on the contents of my experience.
But precisely how much do these two considerations prove? All that is established by the first is the point on which we have already insisted, that it is not my experience which constitutes Reality; and all that is established by the second, that experience, as we have already repeatedly seen, is not merely cognitive. But the admission of both these positions brings us not one step nearer the conclusion which the realist draws from them, that real existence is independent of all experience. Because it is easy to show that the reality of a thing does not depend on its being explicitly recognised by any one finite percipient or any aggregate of finite percipients, and again, that there is more in any experience of finite percipients than those percipients know, the realist thinks he may infer that there are realities which would still be real though they entered into no experience at all. But there is really no logical connection whatever between the premisses of this inference and the conclusion which is drawn from them.
This may be made clearer by a couple of examples. Take, to begin with, the case of the mental life of my fellow human beings. And, to state the case in the form in which it appears most favourable to the realist conclusion, let us imagine an Alexander Selkirk stranded on a barren rock in the midst of the ocean. The hopes and fears of our Selkirk are independent of my knowledge of them just as completely and in just the same sense in which the existence and conformation of the rock on which he is stranded are so. I and all other inhabitants of the earth may be just as ignorant of Selkirk’s existence and of what is passing in his mind as we are of the existence and geological structure of his rock. And again, what Selkirk explicitly cognises of his own inner life may bear as small a proportion to the whole as what he explicitly cognises of the properties of his rock to the whole nature of the rock. Yet all this in no wise shows that Selkirk’s hopes and fears and the rest of his mental life are not experience or have a reality “independent of experience.” Hopes and fears which are not experience, not psychical matter of fact, would indeed be a contradiction in set terms. And what the argument fails to prove of Selkirk’s mental life, it fails, for the same reason, to prove of Selkirk’s rock.
We may pass from the case of the mental life of a fellow-man to the case of unperceived physical reality. A recent realist philosopher, Mr. L. T. Hobhouse, has brought forward as a clear instance of an independent physical reality, the case of a railway train just emerging from a tunnel. I do not perceive the train, he says, until it issues from the tunnel, but it was just as real while it was running through the tunnel. Its reality is therefore independent of the question whether it is perceived or not. But, in the first place, the argument requires that the train shall be empty; it must be a runaway train without driver, guard, or passengers, if the conditions presumed in the premisses are to be fulfilled. And, in the second place, we may retort that even an empty runaway train must have been despatched from somewhere by somebody. It must stand in some relation to the general scheme of purposes and interests expressed in our system of railway traffic, and it is precisely this connection, with a scheme of purposes and interests, which makes the runaway train a reality and not a mere fiction of an ingenious philosopher’s imagination. If Mr. Hobhouse’s argument proves the independent reality of the train in the tunnel, it ought equally to prove, and does equally prove, the independent existence of Selkirk’s fluctuations from hope to despair and back again on his isolated rock. And precisely because it proves both conclusions equally, the sort of independence it establishes cannot be independence of experience. Like all realist arguments, it turns on the identification of experience with the cognitive aspect of experience, an identification too often suggested by the language of the “idealists” themselves.[[48]]