The true analysis of a sensation or idea is as follows. The element that is common to them all, and which I have called "consciousness," really is consciousness. A sensation is, in reality, a case of 'knowing' or 'being aware of' or 'experiencing' something. When we know that the sensation of blue exists, the fact we know is that there exists an awareness of blue. And this awareness is not merely, as we have hitherto seen it must be, itself something distinct and unique, utterly different from blue: it also has a perfectly distinct and unique relation to blue, a relation which is not that of thing or substance to content, nor of one part of content to another part of content. This relation is just that which we mean in every case by 'knowing.' To have in your mind 'knowledge' of blue, is not to have in your mind a 'thing' or 'image' of which blue is the content. To be aware of the sensation of blue is not to be aware of a mental image—of a "thing," of which 'blue' and some other element are constituent parts in the same sense in which blue and glass are constituents of a blue bead. It is to be aware of an awareness of blue; awareness being used, in both cases, in exactly the same sense. This element, we have seen, is certainly neglected by the 'content' theory: that theory entirely fails to express the fact that there is, in the sensation of blue, this unique relation between blue and the other constituent. And what I contend is that this omission is not mere negligence of expression, but is due to the fact that though philosophers have recognised that something distinct is meant by consciousness, they have never yet had a clear conception of what that something is. They have not been able to hold it and blue before their minds and to compare them, in the same way in which they can compare blue and green. And this for the reason I gave above: namely that the moment we try to fix our attention upon consciousness and to see what, distinctly, it is, it seems to vanish: it seems as if we had before us a mere emptiness. When we try to introspect the sensation of blue, all we can see is the blue: the other element is as if it were diaphanous. Yet it can be distinguished if we look attentively enough, and if we know that there is something to look for. My main object in this paragraph has been to try to make the reader see it; but I fear I shall have succeeded very ill.
It being the case, then, that the sensation of blue includes in its analysis, beside blue, both a unique element 'awareness' and a unique relation of this element to blue, I can make plain what I meant by asserting, as two distinct propositions, (1) that blue is probably not part of the content of the sensation at all, and (2) that, even it were, the sensation would nevertheless not be the sensation of blue, if blue had only this relation to it. The first hypothesis may now be expressed by saying that, if it were true, then, when the sensation of blue exists, there exists a blue awareness: offence may be taken at the expression, but yet it expresses just what should be and is meant by saying that blue is, in this case, a content of consciousness or experience. Whether or not, when I have the sensation of blue, my consciousness or awareness is thus blue, my introspection does not enable me to decide with certainty: I only see no reason for thinking that it is. But whether it is or not, the point is unimportant, for introspection does enable me to decide that something else is also true: namely that I am aware of blue, and by this I mean, that my awareness has to blue a quite different and distinct relation. It is possible, I admit, that my awareness is blue as well as being of blue: but what I am quite sure of is that it is of blue; that it has to blue the simple and unique relation the existence of which alone justifies us in distinguishing knowledge of a thing from the thing known, indeed in distinguishing mind from matter. And this result I may express by saying that what is called the content of a sensation is in very truth what I originally called it—the sensation's object.
But, if all this be true, what follows?
Idealists admit that some things really exist of which they are not aware: there are some things, they hold, which are not inseparable aspects of their experience, even if they be inseparable aspects of some experience. They further hold that some of the things of which they are sometimes aware do really exist, even when they are not aware of them: they hold for instance that they are sometimes aware of other minds, which continue to exist even when they are not aware of them. They are, therefore, sometimes aware of something which is not an inseparable aspect of their own experience. They do know some things which are not a mere part or content of their experience. And what my analysis of sensation has been designed to show is, that whenever I have a mere sensation or idea, the fact is that I am then aware of something which is equally and in the same sense not an inseparable aspect of my experience. The awareness which I have maintained to be included in sensation is the very same unique fact which constitutes every kind of knowledge: "blue" is as much an object, and as little a mere content, of my experience, when I experience it, as the most exalted and independent real thing of which I am ever aware. There is, therefore, no question of how we are to "get outside the circle of our own ideas and sensations." Merely to have a sensation is already to be outside that circle. It is to know something which is as truly and really not a part of my experience, as anything which I can ever know.
Now I think I am not mistaken in asserting that the reason why Idealists suppose that everything which is must be an inseparable aspect of some experience, is that they suppose some things, at least, to be inseparable aspects of their experience. And there is certainly nothing which they are so firmly convinced to be an inseparable aspect of their experience as what they call the content of their ideas and sensations. If, therefore, this turns out in every case, whether it be also the content or not, to be at least not an inseparable aspect of the experience of it, it will be readily admitted that nothing else which we experience ever is such an inseparable aspect. But if we never experience anything but what is not an inseparable aspect of that experience, how can we infer that anything whatever, let alone everything, is an inseparable aspect of any experience? How utterly unfounded is the assumption that "esse is percipi" appears in the clearest light.
But further I think it may be seen that if the object of an Idealist's sensation were, as he supposes, not the object but merely the content of that sensation, if, that is to say, it really were an inseparable aspect of his experience, each Idealist could never be aware either of himself or of any other real thing. For the relation of a sensation to its object is certainly the same as that of any other instance of experience to its object; and this, I think, is generally admitted even by Idealists: they state as readily that what is judged or thought or perceived is the content of that judgment or thought or perception, as that blue Is the content of the sensation of blue. But, if so, then when any Idealist thinks he is aware of himself or of any one else, this cannot really be the case. The fact Is, on his own theory, that himself and that other person are in reality mere contents of an awareness, which is aware of nothing whatever. All that can be said is that there is an awareness in him, with a certain content: it can never be true that there is in him a consciousness of anything. And similarly he is never aware either of the fact that he exists or that reality is spiritual. The real fact, which he describes in those terms, is that his existence and the spirituality of reality are contents of an awareness, which is aware of nothing—certainly not, then, of it own content.
And further if everything, of which he thinks he is aware, is in reality merely a content of his own experience he has certainly no reason for holding that anything does exist except himself: it will, of course, be possible that other persons do exist; solipsism will not be necessarily true; but he cannot possibly infer from anything he holds that it is not true. That he himself exists will of course follow from his premiss that many things are contents of his experience. But since everything, of which he thinks himself aware, is in reality merely an inseparable aspect of that awareness; this premiss allows no inference that any of these contents, far less any other consciousness, exists at all except as an inseparable aspect of his awareness, that is, as part of himself.
Such, and not those which he takes to follow from it, are the consequences which do follow from the Idealist's supposition that the object of an experience is in reality merely a content or inseparable aspect of that experience. If, on the other hand, we clearly recognise the nature of that peculiar relation which I have called "awareness of anything"; if we see that this is involved equally in the analysis of every experience—from the merest sensation to the most developed perception or reflexion, and that this is in fact the only essential element in an experience—the only thing that is both common and peculiar to all experiences—the only thing which gives us reason to call any fact mental; if, further, we recognise that this awareness is and must be in all cases of such a nature that its object, when we are aware of it, is precisely what it would be, if we were not aware: then it becomes plain that the existence of a table in space is related to my experience of it in precisely the same way as the existence of my own experience is related to my experience of that. Of both we are merely aware: if we are aware that the one exists, we are aware in precisely the same sense that the other exists; and if it is true that my experience can exist, even when I do not happen to be aware of its existence, we have exactly the same reason for supposing that the table can do so also. When, therefore, Berkeley, supposed that the only thing of which I am directly aware is my own sensations and ideas, he supposed what was false; and when Kant supposed that the objectivity of things in space consisted in the fact that they were "Vorstellungen" having to one another different relations from those which the same "Vorstellungen" have to one another in subjective experience, he supposed what was equally false. I am as directly aware of the existence of material things in space as of my own sensations; and what I am aware of with regard to each is exactly the same—namely that in one case the material thing, and in the other case my sensation does really exist. The question requiring to be asked about material things is thus not: What reason have we for supposing that anything exists corresponding to our sensations? but: What reason have we for supposing that material things do not exist, since their existence has precisely the same evidence as that of our sensations? That either exist may be false; but if it is a reason for doubting the existence of matter, that it is an inseparable aspect of our experience, the same reasoning will prove conclusively that our experience does not exist either, since that must also be an inseparable aspect of our experience of it. The only reasonable alternative to the admission that matter exists as well as spirit, is absolute Scepticism—that, as likely as not nothing exists at all. All other suppositions—the Agnostic's, that something, at all events, does exist, as much as the Idealist's, that spirit does—are, if we have no reason for believing in matter, as baseless as the grossest superstitions.
[1] International Journal of Ethics, October, 1902.