Philosophical Studies · G. E. Moore
SOME JUDGMENTS OF PERCEPTION
I want to raise some childishly simple questions as to what we are doing when we make judgments of a certain kind, which we all do in fact exceedingly commonly make. The kind of judgments I mean are those which we make when, with regard to something which we are seeing, we judge such things as '"That is an inkstand," "That is a tablecloth," "That is a door," etc., etc.; or when, with regard to something which we are feeling with our hands, we judge such things as "This is cloth," "This is a finger," "This is a coin," etc., etc. It is scarcely possible, I think, to exaggerate the frequency with which we make such judgments as these, nor yet the certainty with which we are able to make vast numbers of them. Any man, who is not blind, can, at almost any moment of his waking life, except when he is in the dark, make a large number of judgments of the first kind, with the greatest certainty. He has only to look about him, if he is indoors, to judge with regard to various things which he is seeing, such things as "That is a window," "That is a chair," "This is a book"; or, if he is out-of-doors, such things as "That is a house," "That is a motor-car," "That is a man," or "That is a stone," "That is a tree," "That is a cloud." And all of us, who are not blind, do in fact constantly make such judgments, even if, as a rule, we only make them as parts of more complicated judgments.
What I mean is that, when we make such judgments as "Hullo! that clock has stopped," or "This chair is more comfortable than that one," or "That man looks like a foreigner," judgments of the simpler kind with which I am concerned are, so far as I can see, actually a part of what we are judging. In judging "That clock has stopped," part of what I am actually judging is, so far as I can see, "That is a clock;" and similarly if I judge "That tree is taller than this one," my judgment actually contains the two simpler judgments "That is a tree," and "This is a tree." Perhaps most judgments which we make, of the kind I mean, are, in this way, only parts of more complicated judgments: I do not know whether this is so or not. But in any case there can be no doubt that we make them exceedingly commonly. And even a blind man, or a man in the dark, can and does, very frequently, make judgments of the second kind--judgments about things which he is feeling with his hands. All of us, for instance, at almost any moment of our waking life, whether we are in the dark or not, have only to feel certain parts of our own bodies or of our clothes, in order to make, with great certainty, such judgments as "This is a finger," "This is a nose," "This is cloth." And similarly I have only to feel in my pockets to judge, with regard to objects which I meet with there, such things as "This is a coin," "This is a pencil," "This is a pipe."
Judgments of this kind would, I think, commonly, and rightly, be taken to be judgments, the truth of which involves the existence of material things or physical objects. If I am right in judging that this is an inkstand, it follows that there is at least one inkstand in the Universe; and if there is an inkstand in the Universe, it follows that there is in it at least one material thing or physical object. This may, of course, be disputed. Berkeley, if I understand him rightly, was clearly of opinion that there was no inconsistency in maintaining that there were in the Universe thousands of inkstands and trees and stones and stars, and that yet there was in it no such thing as matter. And perhaps the definition of matter, which he adopted, was such that there really was no inconsistency in maintaining this. Perhaps, similarly, other philosophers have sometimes adopted definitions of the expressions "material things" and "physical objects," which were such that all the judgments of this kind that we make might quite well be true, without its being true that there are in the Universe any material things whatever.
Perhaps, even, there may be some justification for adopting definitions of those terms which would yield the surprising result that we may, with perfect consistency, maintain that the world is full of minerals and vegetables and animals, of all sorts of different kinds, and that yet there is not to be found in it a single material thing. I do not know whether there is or is not any utility in using the terms "material thing" or "physical object" in such a sense as this. But, whether there is or not, I cannot help thinking that there is ample justification for using them in another sense--a sense in which from the proposition that there are in the Universe such things as inkstands or fingers or clouds, it strictly follows that there are in it at least as many material things, and in which, therefore, we can _not_ consistently maintain the existence of inkstands, fingers, and clouds, while denying that of material things. The kinds of judgment which I have mentioned, and thousands of others which might easily be mentioned, are obviously all of the same sort in one very important respect--a respect in which, for instance, such judgments as "This is an emotion," "This is a judgment," "This is a colour," are _not_ of the same sort as they are.
And it seems to me that we are certainly using the term "material thing" in _a_ correct and useful way, if we express this important common property which they have, by saying that of each of them the same can truly be said as was said of the judgment "That is an inkstand": that, just as from the proposition "There is an inkstand" it follows that there is at least one material thing, so from the proposition "There is a tablecloth," it follows that there is at least one material thing; and similarly in all the other cases. We can certainly use the expression "Things _such as_ inkstands, tablecloths, fingers, clouds, stars, etc.," to mean things such as these in a certain very important respect, which we all understand, though we may not be able to define it. And the term "material thing" certainly is and can be correctly used to mean simply things such as these in that respect--whatever it may be. Some term is certainly required to mean merely things such as these in that important respect; and, so far as I can see, there is no term which can be naturally used in this sense except the term "material things" and its equivalents. Thus understood, the term "material thing" certainly does stand for an important notion, which requires a name.
And, if we agree to use the term in this sense, then it is obvious that no more can be necessary for the truth of the assertion that there are material things, than is necessary for the truth of judgments of the kind with which I propose to deal. But no more can be necessary for the truth of these judgments than is actually asserted in or logically implied by them. And if we approach the question what is necessary for the truth of the assertion that there are material things, by asking what it is that we actually assert when we make such judgments as these, certain reasons for doubting how much is necessary are, I think, brought out much more clearly, than if we approach the question in any other way. Many philosophers have told us a very great deal as to what they suppose to be involved in the existence of material things; and some, at least, among them seem to have meant by "material things" such things as inkstands, fingers and clouds.
But I can think of only one type of view as to the constitution of material things, which is such that it is tolerably clear what answer those who hold it would give to the simple question; What is it that I am judging, when I judge, as I now do, that that is an inkstand? The type of view I mean is that to which the view that Mill suggests, when he explains what he means by saying that Matter is a Permanent Possibility of Sensation, and also the view or views which Mr. Russell seems to suggest in his "Our Knowledge of the External World," seem to belong. In the case of views of this kind, it is, I think, tolerably clear what answer those who hold them would give to _all_ the questions I want to raise about judgments of the kind I have described. But it does not seem to me at all certain that any view of this type is true; and certainly many philosophers have held and do hold that all views of this type are false. But in the case of those who do hold them to be false, I do not know, in any single case, what answer would be given to _all_ the questions which I want to raise.
In the case of philosophers, who do not accept any view of the Mill-Russell type, none, so far as I know, has made it clear what answer he would give to _all_ my questions: some have made it clear what answer they would give to _some_ of them; but many, I think, have not even made it clear what answer they would give to any. Perhaps there is some simple and satisfactory answer, which has escaped me, that such philosophers could give to all my questions; but I cannot help thinking that assumptions as to the nature of material things have too often been made, without its even occurring to those who made them to ask, what, if they were true, we could be judging when we make such judgments as these; and that, if this question had been asked, it would have become evident that those assumptions were far less certain than they appeared to be.
I do not know that there is any excuse whatever for calling _all_ judgments of the kind I mean "judgments of perception." All of them are, of course, judgments _about_ things which we are at the moment perceiving, since, by definition, they are judgments about things which we are seeing or feeling with our hands; and all of them are, no doubt, also _based upon_ something which we perceive about the thing in question. But the mere fact that a judgment is both about a thing which I am perceiving, and also based upon something which I perceive about that thing, does not seem to be a sufficient reason for calling it a judgment of perception; and I do not know that there is any other reason than this for calling _all_ judgments of the kind I mean judgments of perception. I do not want therefore, to assert that _all_ of them are so. But it seems to me quite plain that enormous numbers of them are so, in a perfectly legitimate sense.
This judgment, which I now make, to the effect that _that_ is a door, seems to me quite plainly to be a judgment of perception, in the simple sense that I make it because I do, in fact, see that that _is_ a door, and assert in it no more than what I see; and what I see I, of course, perceive. In every case in which I judge, with regard to something which I am seeing or feeling with my hands, that it is a so-and-so, simply because I do perceive, by sight or touch, that it is in fact a thing of that kind, we can, I think, fairly say that the judgment in question is a judgment of perception. And enormous numbers of judgments of the kind I mean are, quite plainly, judgments of perception in this sense. They are not _all,_ for the simple reason that some of them are mistaken. I may, for instance, judge, with regard to an animal which I see at a distance, that it is a sheep, when in fact it is a pig. And here my judgment is certainly not due to the fact that I see it to be a sheep; since I cannot possibly see a thing to be a sheep, unless it is one.
It, therefore, is _not_ a judgment of perception in this sense. And moreover, even where such a judgment is true, it may not always be a judgment of perception, for the reason that, whereas I only see the thing in question, the kind of thing which I judge it to be is of such a nature, that it is impossible for any one, by sight alone, to perceive anything to be of that kind. How to draw the line between judgments of this kind, which are judgments of perception, and those which are not, I do not know. That is to say, I do not know what conditions must be fulfilled in order that I may be truly said to be _perceiving,_ by sight or touch, such things as that that is a door, this is a finger, and not _merely_ inferring them. Some people may no doubt think that it is very unphilosophical in me to say that we _ever_ can perceive such things as these. But it seems to me that we do, in ordinary life, constantly talk of _seeing_ such things, and that, when we do so, we are neither using language incorrectly, nor making any mistake about the facts--supposing something to occur which never does in fact occur.
The truth seems to me to be that we are using the term "perceive" in a way which is both perfectly correct and expresses a kind of thing which constantly does occur, only that some philosophers have not recognised that this is a correct usage of the term and have not been able to define it. I am not, therefore, afraid to say that I do now perceive that that is a door, and that that is a finger. Only, of course, when I say that I do, I do not mean to assert that part of what I "perceive," when I "perceive" these things, may not be something which, in an important sense, is known to me only by inference. It would be very rash to assert that "perception," in this sense of the word, entirely excludes inference. All that seems to me certain is that there is an important and useful sense of the word "perception," which is such that the amount and kind of inference, if inference there be, which is involved in my present perception that that is a door, is no bar to the truth of the assertion that I do perceive that it is one. Vast numbers, then, of the kind of judgments with which I propose to deal seem to me to be, in an important and legitimate sense, judgments of perception; although I am not prepared to define, any further than I have done, what that sense is. And though it is true that the questions which I shall raise apply just as much to those of them which are not judgments of perception as to those which are, it is, of course, also true that they apply just as much to those which are as to those which are not; so that I shall be really dealing with a large and important class among judgments of perception.
It is true that, if certain views which, if I understand them rightly, some Philosophers have seriously entertained, were true ones, it would be quite impossible that any of them should be judgments of perception. For some philosophers seem to me to have denied that we ever do in fact know such things as these, and others not only that we ever know them but also that they are ever true. And, if, in fact, I never do know such a thing, or if it is never true, it will of course, follow that I never perceive such a thing; since I certainly cannot, in this sense, perceive anything whatever, unless I both know it and it is true. But it seems to me a sufficient refutation of such views as these, simply to point to cases in which we do know such things. This, after all, you know, really is a finger: there is no doubt about it: I know it, and you all know it. And I think we may safely challenge any philosopher to bring forward any argument in favour either of the proposition that we do not know it, or of the proposition that it is not true, which does not at some point, rest upon some premiss which is, beyond comparison, less certain than is the proposition which it is designed to attack. The questions whether we do ever know such things as these, and whether there are any material things, seem to me, therefore, to be questions which there is no need to take seriously: they are questions which it is quite easy to answer, with certainty, in the affirmative. What does, I think, need to be taken seriously, and what is really dubious, is not the question, whether this is a finger, or whether I know that it is, but the question _what,_ in certain respects, I am knowing, when I know that it is. And this is the question to which I will now address myself.
To begin with there is one thing which seems to me to be very certain indeed about such judgments. It is unfortunately a thing which I do not know how properly to express. There seem to me to be objections to every way of expressing it which I can think of. But I hope I may be able to make my meaning clear, in spite of the inadequacy of my expression. The thing I mean is a thing which may to some people seem so obvious as to be scarcely worth saying. But I cannot help thinking that it is not always clearly recognised, and even that some philosophers, to judge from what they say, might perhaps dispute it. It seems to me to be an assumption which is silently made in many treatments of the subject, and, as I say, it seems to me to be very certain indeed. But I think it is at all events worth while to try to make the assumption explicit, in case it should be disputed. If it really is not true, then the other questions to which I shall go on, and which seem to me really dubious and difficult, do not, I think, arise at all.
I will try to express this fundamental assumption, which seems to me so very certain, by saying it is the assumption that, in all cases in which I make a judgment of this sort, I have no difficulty whatever in picking out a thing, which is, quite plainly, in a sense in which nothing else is, _the_ thing about which I am making my judgment; and that yet, though this thing is _the_ thing about which I am judging, I am, quite certainly, _not_, in general, judging with regard to it, that _it_ is a thing of that kind for which the term, which seems to express the predicate of my judgment, is a name. Thus, when I judge, as now, that That is an inkstand, I have no difficulty whatever in picking out, from what, if you like, you can call my total field of presentation at the moment, an object, which is undoubtedly, in a sense in which nothing else is, _the_ object about which I am making this judgment; and yet it seems to me quite certain that of _this_ object I am not judging that it is a whole inkstand.
And similarly when I judge, with regard to something which I am feeling in my pocket, "This is a coin," I have no difficulty in picking out, from my field of presentation, an object, which is undoubtedly _the_ object with which my judgment is concerned; and yet I am certainly not judging with regard to this object that it is a whole coin. I say that _always__t_ when I make such a judgment, I can pick out _the_ one, among the objects presented to me at the time, about which I am making it; but I have only said that _in general_ I am not judging with regard to this object that it is a thing of the kind, for which the term, which seems to express the predicate of my judgment, is a name. And I have limited my second proposition in this way, because there are cases, in which it does not, at first sight, seem quite so certain that I am not doing this, as in the two instances I have just given.
When, for instance, I judge with regard to something, which I am seeing, "This is a soap-bubble," or "This is a drop of water," or even when I judge "This is a spot of ink," it may not seem quite so plain, that I may not be judging, with regard to the very object presented to me, that it is, itself, a whole soap-bubble, a whole drop of water, or a whole spot of ink, as it always is, in the case of an inkstand, or a coin, that I never take the presented object, about which I am judging, to be a whole inkstand, or a whole coin. The sort of reason why I say this will, of course, be obvious to any one, and it is obviously of a childish order. But I cannot say that it seems to me quite obvious that in such a case I am not judging of the presented object that it is a whole drop of water, in the way in which it does seem to be obvious that I am not judging of _this_ presented object that it is an inkstand.
That is why I limit myself to saying that, _in general_, when I judge "That is a so-and-so" I am not judging with regard to the presented object, about which my judgment is that _it_ is a thing of the kind in question. As much as this seems to me to be a thing which any child can see. Nobody will suppose, for a moment, that when he judges such things as "This is a sofa," or "This is a tree," he is judging, with regard to the presented object about which his judgment plainly is, that it is a whole sofa or a whole tree: he can, at most, suppose that he is judging it to be a part of the surface of a sofa or a part of the surface of a tree. And certainly in the case of most judgments of this kind which we make, whether in the case of all or not, this is plainly the case: we are not judging, with regard to the presented object about which our judgment plainly is, that it is a thing of the kind, for which the term which appears to express the predicate of our judgment, is a name. And that this should be true of _most_ judgments of this kind, whether of all or not, is quite sufficient for my purpose.
This much, then, seems to me to be very certain indeed. But I will try to make clearer exactly what I mean by it, by mentioning a ground on which I imagine it might perhaps be disputed. The object of which I have spoken as _the_ object, about which, in each particular case, such a judgment as this always is a judgment, is, of course, always an object of the kind which some philosophers would call a sensation, and others would call a sense-datum. Whether all philosophers, when they talk of sensations, mean to include among them such objects as these, I do not know. Some, who have given a great deal of attention to the subject, and for whom I have a great respect, talk of sensations in such a way, that I cannot be sure what they are talking about at all or whether there are such things. But many, I think, undoubtedly do mean to include such subjects as these. No doubt, in general, when they call them sensations, they mean to attribute to them properties, which it seems to me extremely doubtful whether they possess. And perhaps even those who call them sense-data, may, in part, be attributing to them properties which it may be doubtful whether they possess. If we want to define a sensation or a sense-datum, in a manner which will leave it not open to doubt what sort of things we are talking of, and that there are such things, I do not know that we can do it better than by saying that sense-data are the sort of things, _about_ which such judgments as these always seem to be made--the sort of things which seem to be the real or ultimate subjects of all such judgments. Such a way of defining how the term "sense-datum" is used, may not seem very satisfactory; but I am inclined to think it may be as satisfactory as any which can be found. And it is certainly calculated to obviate some misunderstandings which may arise; since everybody can see, I think, what the thing is which I am describing as _the_ thing about which he is making his judgment, when he judges "That is an inkstand," and that there is such a thing, even if he does not agree that this description applies to it.
Ideas discussed in this chapter
Text from Project Gutenberg, public domain in the United States.