I do not wish, just now, to discuss the nature of attention; I wish only to point out that it enables us to take the first steps in abstraction. Out of the whole multiplicity of objects of sense, it enables us to single out a small selection, which is an indispensable preliminary to abstraction. For example, attention will enable us to discriminate a coloured pattern which we are seeing, and to separate it from the other things we see and from images and other objects of sense and thoughts which may exist simultaneously. For the sake of simplicity, let us suppose that we discriminate a black and white pattern in the form of a triangle. Within this pattern we can further discriminate sides and angles and an inside and outside—of course the sides are not mathematical lines nor the angles mathematical points.
We now come to a question of very great importance, upon which our views of the relations of mind and matter largely depend. The question is this:
What difference is there between the propositions “there is a triangle” and “I see a triangle”?
Both these statements seem as certain as any statement can be—at least if rightly interpreted. As always happens in such cases, we are quite certain of something, but not quite certain what it is that we are certain of. I want to ask whether this something that we are certain of is really different in the above two statements, or whether the difference between them is only as to surroundings of which we are not certain. Most philosophers hold that there is a difference in what we are certain of; Mach, James, Dewey, the American realists, and I hold that the difference is in the uncertain context. Let us examine this question.
The suggestions of the two statements “I see a triangle” and “there is a triangle” are obviously different. The first states an event in my life, and suggests its possible effects upon me. The second aims at stating an event in the world, supposed to be equally discoverable by other people. You might say “there is a triangle” if you had seen it a moment ago but now had your eyes shut; in this case you would not say “I see a triangle”. On the other hand, one sometimes, under the influence of indigestion or fatigue, sees little black dots floating in the air; in such circumstances you would say “I see a black dot”, but not “there is a black dot”. This illustration shows that when you say “there is a black dot” you are making a stronger assertion than when you say “I see a black dot”. In the other case, when you say “there is a triangle” because you saw it a moment ago, though not now, you have three stages: First, memory assures you of the proposition “I saw a triangle”, and then you pass on to “there was a triangle”, and then, further, to “there is a triangle, because nothing can have happened to destroy it so quickly.” Here we have obviously passed far beyond the region of immediate certainty.
It seems clear, therefore, that, of our two statements, the one which comes nearest to expressing the fact of which we are immediately certain is “I see a triangle”, because the other makes inferences to something public, and thus goes beyond the bare datum. This is on the assumption that we should not say “there is a black dot” when we see a black dot which we attribute to eye-trouble and therefore suppose that no one else can see. Let us therefore concentrate upon “I see a triangle”, and ask ourselves whether the whole of this, or only part, can be accepted as a primitive certainty.
A moment’s reflection shows that both “I” and “see” are words which take us beyond what the momentary event reveals. Take “I” to begin with. This is a word whose meaning evidently depends upon memory and expectation. “I” means the person who had certain remembered experiences and is expected to have certain future experiences. We might say “I see a triangle now and I saw a square a moment ago.” The word “I” has exactly the same meaning in its two occurrences in this sentence, and therefore evidently has a meaning dependent upon memory. Now it is our object to arrive at the contribution to your knowledge which is made by seeing the triangle at the moment. Therefore, since the word “I” takes you beyond this contribution, we must cut it out if we want to find a correct verbal expression for what is added to our knowledge by seeing the triangle. We will say “a triangle is being seen”. This is at any rate one step nearer to what we are seeking.
But now we must deal with the word “seen”. As ordinarily used, this is a causal word, suggesting something dependent upon the eyes. In this sense, it obviously involves a mass of previous experience; a new-born baby does not know that what it sees depends upon its eyes. However, we could eliminate this. Obviously all objects of sight have a common quality, which no objects of touch or hearing have; a visual object is different from an auditory object, and so on. Therefore instead of saying “a triangle is being seen”, we should say “there is a visual triangle”. Of course the meanings of the words “visual” and “triangle” can only be learnt by experience, but they are not logically dependent upon experience. A being could be imagined which would know the words at birth; such a being could express its datum in the words “there is a visual triangle”. In any case, the problems remaining belong to the study of concepts; we will therefore ignore them at present.
Now in English the words “there is” are ambiguous. When I used them before, saying, “there is a triangle”, I meant them in the sense of “voila” or “da ist”. Now I mean them in the sense of “il y a” or “es giebt”. One might express what is meant by saying “a visual triangle exists”, but the word “exist” has all sorts of metaphysical connotations that I wish to avoid. Perhaps it is best to say “occurs”.
We have now arrived at something which is just as true when your perception is illusory as when it is correct. If you say “a visual black dot is occurring”, you are speaking the truth, if there is one in your field of vision. We have eliminated the suggestion that others could see it, or that it could be touched, or that it is composed of matter in the sense of physics. All these suggestions are present when one says, in ordinary conversation, “there is a black dot”; they are intended to be eliminated by the addition of the word “visual” and the substitution of “is occurring” for “there is”. By these means we have arrived at what is indubitable and intrinsic in the addition to your knowledge derived from a visual datum.