Appearance and Reality

Is there any knowledge in the world which is so certain that no reasonable man could doubt it? This question, which at first sight might not seem difficult, is really one of the most difficult that can be asked. When we have realized the obstacles in the way of a straightforward and confident answer, we shall be well launched on the study of philosophy—for philosophy is merely the attempt to answer such ultimate questions, not carelessly and dogmatically, as we do in ordinary life and even in the sciences, but critically, after exploring all that makes such questions puzzling, and after realizing all the vagueness and confusion that underlie our ordinary ideas.

Is there any knowledge in the world so certain that no reasonable person could doubt it? At first, this question might not seem difficult. But it is really one of the most difficult questions we can ask. Once we understand the obstacles to a straightforward, confident answer, we will be well into the study of philosophy. For philosophy is simply the attempt to answer such fundamental questions critically, rather than carelessly and dogmatically. We take the careless, dogmatic approach in everyday life and even in the sciences. But philosophy first explores everything that makes such questions puzzling. It also recognizes all the vagueness and confusion underlying our everyday ideas.

In daily life, we assume as certain many things which, on a closer scrutiny, are found to be so full of apparent contradictions that only a great amount of thought enables us to know what it is that we really may believe. In the search for certainty, it is natural to begin with our present experiences, and in some sense, no doubt, knowledge is to be derived from them. But any statement as to what it is that our immediate experiences make us know is very likely to be wrong. It seems to me that I am now sitting in a chair, at a table of a certain shape, on which I see sheets of paper with writing or print. By turning my head I see out of the window buildings and clouds and the sun. I believe that the sun is about ninety-three million miles from the earth; that it is a hot globe many times bigger than the earth; that, owing to the earth's rotation, it rises every morning, and will continue to do so for an indefinite time in the future. I believe that, if any other normal person comes into my room, he will see the same chairs and tables and books and papers as I see, and that the table which I see is the same as the table which I feel pressing against my arm. All this seems to be so evident as to be hardly worth stating, except in answer to a man who doubts whether I know anything. Yet all this may be reasonably doubted, and all of it requires much careful discussion before we can be sure that we have stated it in a form that is wholly true.

In daily life, we take many things as certain. But a closer look reveals so many apparent contradictions that understanding what we can really believe takes considerable thought. In searching for certainty, it is natural to begin with our present experiences. In some sense, knowledge must no doubt come from those experiences. But any claim about what our immediate experiences tell us is very likely to be wrong. I seem to be sitting in a chair, at a table of a particular shape. On the table, I see sheets of paper with writing or print on them. When I turn my head, I see buildings, clouds, and the sun through the window. I believe the sun is about ninety-three million miles from the earth. I believe it is a hot globe many times larger than the earth. I believe the sun rises every morning because of the earth's rotation. I also believe it will continue to rise for an indefinite time into the future. I believe that if any other person with normal perception enters my room, they will see what I see: the same chairs, tables, books, and papers. I also believe the table I see is the same table I feel pressing against my arm. All these beliefs seem so obvious that they are hardly worth stating, except to someone who doubts whether I know anything. Yet all these beliefs can reasonably be doubted. Each requires much careful discussion before we can be sure we have expressed it in a completely true form.

To make our difficulties plain, let us concentrate attention on the table. To the eye it is oblong, brown and shiny, to the touch it is smooth and cool and hard; when I tap it, it gives out a wooden sound. Any one else who sees and feels and hears the table will agree with this description, so that it might seem as if no difficulty would arise; but as soon as we try to be more precise our troubles begin. Although I believe that the table is 'really' of the same colour all over, the parts that reflect the light look much brighter than the other parts, and some parts look white because of reflected light. I know that, if I move, the parts that reflect the light will be different, so that the apparent distribution of colours on the table will change. It follows that if several people are looking at the table at the same moment, no two of them will see exactly the same distribution of colours, because no two can see it from exactly the same point of view, and any change in the point of view makes some change in the way the light is reflected.

To make our difficulties clear, let us focus on the table. It looks oblong, brown, and shiny. To the touch, it is smooth, cool, and hard. When I tap it, it makes a wooden sound. Anyone else who sees, touches, and hears the table will agree with this description. So it might seem as if there would be no difficulty. But as soon as we try to be more precise, our troubles begin. Although I believe the table is 'really' the same colour all over, the parts reflecting light look much brighter. Some parts look white because of reflected light. I know that if I move, different parts will reflect the light. So the apparent pattern of colours on the table will change. It follows that if several people look at the table at the same moment, each will see a different pattern of colours. This is because no two people can see the table from exactly the same viewpoint. And any change in viewpoint changes how the light is reflected.

For most practical purposes these differences are unimportant, but to the painter they are all-important: the painter has to unlearn the habit of thinking that things seem to have the colour which common sense says they 'really' have, and to learn the habit of seeing things as they appear. Here we have already the beginning of one of the distinctions that cause most trouble in philosophy—the distinction between 'appearance' and 'reality', between what things seem to be and what they are. The painter wants to know what things seem to be, the practical man and the philosopher want to know what they are; but the philosopher's wish to know this is stronger than the practical man's, and is more troubled by knowledge as to the difficulties of answering the question.

For most practical purposes, these differences are unimportant, but to the painter they are all-important. The painter must unlearn the habit of thinking that things look the colour common sense says they 'really' are. Instead, the painter must learn to see things as they appear. Here we already begin to see one of the distinctions that cause the most trouble in philosophy. This is the distinction between 'appearance' and 'reality', between what things seem to be and what they are. The painter wants to know what things seem to be. The practical person and the philosopher want to know what things are. But the philosopher's desire to know is stronger than the practical person's. The philosopher is also more troubled by knowing how difficult the question is to answer.

To return to the table. It is evident from what we have found, that there is no colour which pre-eminently appears to be the colour of the table, or even of any one particular part of the table—it appears to be of different colours from different points of view, and there is no reason for regarding some of these as more really its colour than others. And we know that even from a given point of view the colour will seem different by artificial light, or to a colour-blind man, or to a man wearing blue spectacles, while in the dark there will be no colour at all, though to touch and hearing the table will be unchanged. This colour is not something which is inherent in the table, but something depending upon the table and the spectator and the way the light falls on the table. When, in ordinary life, we speak of the colour of the table, we only mean the sort of colour which it will seem to have to a normal spectator from an ordinary point of view under usual conditions of light. But the other colours which appear under other conditions have just as good a right to be considered real; and therefore, to avoid favouritism, we are compelled to deny that, in itself, the table has any one particular colour.

Let us return to the table. What we have found makes one thing clear: no colour stands out as the colour of the table. Nor does any colour stand out as the colour of any particular part of the table. The table appears to have different colours from different viewpoints. There is no reason to consider some of these colours more truly its colour than others. And we know that even from the same viewpoint, the colour will look different under artificial light. The colour will also look different to a colour-blind man or a man wearing blue glasses. In the dark, there will be no colour at all, though the table will remain unchanged to touch and hearing. So the colour is not something the table has in itself. Instead, the colour depends on the table, the viewer, and how the light falls on the table. In everyday life, we speak of the colour of the table. We mean only the colour a viewer with normal vision would see from an ordinary viewpoint under usual lighting conditions. But the colours that appear under other conditions have just as much right to be considered real. So, to avoid favouring one colour over another, we must deny that the table itself has any one particular colour.

The same thing applies to the texture. With the naked eye one can see the grain, but otherwise the table looks smooth and even. If we looked at it through a microscope, we should see roughnesses and hills and valleys, and all sorts of differences that are imperceptible to the naked eye. Which of these is the 'real' table? We are naturally tempted to say that what we see through the microscope is more real, but that in turn would be changed by a still more powerful microscope. If, then, we cannot trust what we see with the naked eye, why should we trust what we see through a microscope? Thus, again, the confidence in our senses with which we began deserts us.

The same applies to the texture. With the naked eye, we can see the grain, but otherwise the table looks smooth and even. If we looked at the table through a microscope, we would see rough patches, hills, and valleys. We would also see all sorts of differences invisible to the naked eye. Which of these views shows the 'real' table? We are naturally tempted to say that what we see through the microscope is more real. But an even more powerful microscope would change that view in turn. If we cannot trust what we see with the naked eye, why should we trust what we see through a microscope? So, once again, we lose the confidence in our senses that we started with.

The shape of the table is no better. We are all in the habit of judging as to the 'real' shapes of things, and we do this so unreflectingly that we come to think we actually see the real shapes. But, in fact, as we all have to learn if we try to draw, a given thing looks different in shape from every different point of view. If our table is 'really' rectangular, it will look, from almost all points of view, as if it had two acute angles and two obtuse angles. If opposite sides are parallel, they will look as if they converged to a point away from the spectator; if they are of equal length, they will look as if the nearer side were longer. All these things are not commonly noticed in looking at a table, because experience has taught us to construct the 'real' shape from the apparent shape, and the 'real' shape is what interests us as practical men. But the 'real' shape is not what we see; it is something inferred from what we see. And what we see is constantly changing in shape as we move about the room; so that here again the senses seem not to give us the truth about the table itself, but only about the appearance of the table.

The table’s shape is no better. We are all used to judging the 'real' shapes of things. We do so without thinking, until we believe we actually see those real shapes. But in fact, an object looks different in shape from every different viewpoint. We all have to learn this if we try to draw. If our table is 'really' rectangular, it will look different from almost every viewpoint. It will appear to have two acute angles and two obtuse angles. If opposite sides are parallel, they will look as if they meet at a point farther from the viewer. If the sides are equal in length, the nearer side will look longer. We do not usually notice these effects when looking at a table. This is because experience has taught us to work out the 'real' shape from the apparent shape. And the 'real' shape is what interests us in practical life. But the 'real' shape is not what we see. We infer that shape from what we see. And the shape we see keeps changing as we move around the room. So here again, our senses seem not to tell us the truth about the table itself, but only about its appearance.

Similar difficulties arise when we consider the sense of touch. It is true that the table always gives us a sensation of hardness, and we feel that it resists pressure. But the sensation we obtain depends upon how hard we press the table and also upon what part of the body we press with; thus the various sensations due to various pressures or various parts of the body cannot be supposed to reveal directly any definite property of the table, but at most to be signs of some property which perhaps causes all the sensations, but is not actually apparent in any of them. And the same applies still more obviously to the sounds which can be elicited by rapping the table.

Similar difficulties arise when we consider our sense of touch. The table does always feel hard, and we feel it resisting pressure. But the sensation depends on how hard we press the table and what part of the body we use. So these different sensations cannot be assumed to directly reveal any definite property of the table. At most, the sensations can be signs of some property that perhaps causes all the sensations. But that property is not actually apparent in any of them. The same applies even more obviously to the sounds we can produce by knocking on the table.

Thus it becomes evident that the real table, if there is one, is not the same as what we immediately experience by sight or touch or hearing. The real table, if there is one, is not immediately known to us at all, but must be an inference from what is immediately known. Hence, two very difficult questions at once arise; namely, (1) Is there a real table at all? (2) If so, what sort of object can it be?

So it becomes clear that the real table, if there is one, differs from what we directly experience through sight, touch, or hearing. The real table, if there is one, is not known to us directly at all. Instead, we must infer it from what we know directly. So two very difficult questions immediately arise: (1) Is there a real table at all? (2) If so, what kind of object can it be?

It will help us in considering these questions to have a few simple terms of which the meaning is definite and clear. Let us give the name of 'sense-data' to the things that are immediately known in sensation: such things as colours, sounds, smells, hardnesses, roughnesses, and so on. We shall give the name 'sensation' to the experience of being immediately aware of these things. Thus, whenever we see a colour, we have a sensation of the colour, but the colour itself is a sense-datum, not a sensation. The colour is that of which we are immediately aware, and the awareness itself is the sensation. It is plain that if we are to know anything about the table, it must be by means of the sense-data—brown colour, oblong shape, smoothness, etc.—which we associate with the table; but, for the reasons which have been given, we cannot say that the table is the sense-data, or even that the sense-data are directly properties of the table. Thus a problem arises as to the relation of the sense-data to the real table, supposing there is such a thing.

To help us consider these questions, we need a few simple terms with clear, precise meanings. Let us use 'sense-data' for the things we know directly through our senses: colours, sounds, smells, hardness, roughness, and so on. We will use 'sensation' for the experience of being directly aware of these things. So whenever we see a colour, we have a sensation of the colour. But the colour itself is a sense-datum, not a sensation. The colour is what we are directly aware of, and the awareness itself is the sensation. Clearly, if we are to know anything about the table, we must do so through sense-data. These are the brown colour, oblong shape, smoothness, and so on that we associate with the table. But for the reasons already given, we cannot say that the table is the sense-data. Nor can we even say that the sense-data are direct properties of the table. So a problem arises: how do the sense-data relate to the real table, supposing there is such a thing?

The real table, if it exists, we will call a 'physical object'. Thus we have to consider the relation of sense-data to physical objects. The collection of all physical objects is called 'matter'. Thus our two questions may be re-stated as follows: (1) Is there any such thing as matter? (2) If so, what is its nature?

If the real table exists, we will call it a 'physical object'. So we need to consider how sense-data relate to physical objects. All physical objects together are called 'matter'. So we can restate our two questions as follows: (1) Is there such a thing as matter? (2) If so, what is the nature of matter?

The philosopher who first brought prominently forward the reasons for regarding the immediate objects of our senses as not existing independently of us was Bishop Berkeley (1685-1753). His Three Dialogues between Hylas and Philonous, in Opposition to Sceptics and Atheists, undertake to prove that there is no such thing as matter at all, and that the world consists of nothing but minds and their ideas. Hylas has hitherto believed in matter, but he is no match for Philonous, who mercilessly drives him into contradictions and paradoxes, and makes his own denial of matter seem, in the end, as if it were almost common sense. The arguments employed are of very different value: some are important and sound, others are confused or quibbling. But Berkeley retains the merit of having shown that the existence of matter is capable of being denied without absurdity, and that if there are any things that exist independently of us they cannot be the immediate objects of our sensations.

Bishop Berkeley (1685-1753) was the first philosopher to give prominence to certain reasons concerning the immediate objects of our senses. These were reasons for thinking those objects do not exist independently of us. His Three Dialogues between Hylas and Philonous, in Opposition to Sceptics and Atheists, sets out to prove that matter does not exist at all. It argues that the world consists only of minds and their ideas. Hylas has believed in matter until now, but he is no match for Philonous. Philonous mercilessly leads Hylas into contradictions and paradoxes. In the end, Philonous makes his own denial of matter seem almost like common sense. The arguments vary greatly in quality: some are important and sound, while others are confused or rely on quibbling. But Berkeley deserves credit for showing that denying the existence of matter need not be absurd. He also showed that if anything exists independently of us, it cannot be an immediate object of our sensations.

There are two different questions involved when we ask whether matter exists, and it is important to keep them clear. We commonly mean by 'matter' something which is opposed to 'mind', something which we think of as occupying space and as radically incapable of any sort of thought or consciousness. It is chiefly in this sense that Berkeley denies matter; that is to say, he does not deny that the sense-data which we commonly take as signs of the existence of the table are really signs of the existence of something independent of us, but he does deny that this something is non-mental, that it is neither mind nor ideas entertained by some mind. He admits that there must be something which continues to exist when we go out of the room or shut our eyes, and that what we call seeing the table does really give us reason for believing in something which persists even when we are not seeing it. But he thinks that this something cannot be radically different in nature from what we see, and cannot be independent of seeing altogether, though it must be independent of our seeing. He is thus led to regard the 'real' table as an idea in the mind of God. Such an idea has the required permanence and independence of ourselves, without being—as matter would otherwise be—something quite unknowable, in the sense that we can only infer it, and can never be directly and immediately aware of it.

Asking whether matter exists involves two different questions, and we must keep them separate. By 'matter', we usually mean something opposed to 'mind'. We think of matter as occupying space and being completely incapable of thought or consciousness. Berkeley denies matter chiefly in this sense. We commonly take sense-data as signs that the table exists. Berkeley does not deny that these sense-data really indicate the existence of something independent of us. But he denies that this something is non-mental, neither a mind nor ideas held in some mind. He accepts that something must continue to exist when we leave the room or close our eyes. He also accepts that seeing the table gives us reason to believe in something that persists when we are not looking. But he thinks this something cannot be fundamentally different in nature from what we see. Nor can its existence be entirely independent of being seen, though it must be independent of our seeing. He therefore regards the 'real' table as an idea in the mind of God. Such an idea has the necessary permanence and independence from us. Yet it avoids being something entirely unknowable, as matter would otherwise be. We could only infer the existence of such matter, never be directly and immediately aware of it.

Other philosophers since Berkeley have also held that, although the table does not depend for its existence upon being seen by me, it does depend upon being seen (or otherwise apprehended in sensation) by some mind—not necessarily the mind of God, but more often the whole collective mind of the universe. This they hold, as Berkeley does, chiefly because they think there can be nothing real—or at any rate nothing known to be real except minds and their thoughts and feelings. We might state the argument by which they support their view in some such way as this: 'Whatever can be thought of is an idea in the mind of the person thinking of it; therefore nothing can be thought of except ideas in minds; therefore anything else is inconceivable, and what is inconceivable cannot exist.'

Other philosophers since Berkeley have also argued that the table does not depend on my seeing it to exist. But the table does depend on being seen (or otherwise perceived through the senses) by some mind. This need not be the mind of God. More often, these philosophers mean the collective mind of the entire universe. Like Berkeley, they hold this view mainly because they think nothing can be real except minds, their thoughts, and their feelings. Or at least, nothing else can be known to be real. We might express their argument roughly like this: 'Whatever someone can think of is an idea in that person's mind. Therefore, nothing can be thought of except ideas in minds. Therefore, anything else is inconceivable, and what is inconceivable cannot exist.'

Such an argument, in my opinion, is fallacious; and of course those who advance it do not put it so shortly or so crudely. But whether valid or not, the argument has been very widely advanced in one form or another; and very many philosophers, perhaps a majority, have held that there is nothing real except minds and their ideas. Such philosophers are called 'idealists'. When they come to explaining matter, they either say, like Berkeley, that matter is really nothing but a collection of ideas, or they say, like Leibniz (1646-1716), that what appears as matter is really a collection of more or less rudimentary minds.

In my opinion, such an argument is flawed. Of course, those who make the argument do not present it so briefly or so crudely. But whether valid or not, the argument has been widely used in one form or another. And very many philosophers, perhaps a majority, have held that nothing is real except minds and their ideas. Such philosophers are called 'idealists'. When explaining matter, idealists take one of two views. Like Berkeley, some say that matter is really nothing but a collection of ideas. Or, like Leibniz (1646-1716), they say that what appears to be matter is really a collection of minds. These minds are more or less basic.

But these philosophers, though they deny matter as opposed to mind, nevertheless, in another sense, admit matter. It will be remembered that we asked two questions; namely, (1) Is there a real table at all? (2) If so, what sort of object can it be? Now both Berkeley and Leibniz admit that there is a real table, but Berkeley says it is certain ideas in the mind of God, and Leibniz says it is a colony of souls. Thus both of them answer our first question in the affirmative, and only diverge from the views of ordinary mortals in their answer to our second question. In fact, almost all philosophers seem to be agreed that there is a real table: they almost all agree that, however much our sense-data—colour, shape, smoothness, etc.—may depend upon us, yet their occurrence is a sign of something existing independently of us, something differing, perhaps, completely from our sense-data, and yet to be regarded as causing those sense-data whenever we are in a suitable relation to the real table.

But although these philosophers deny that matter exists as something distinct from mind, they still accept matter in another sense. Recall the two questions we asked: (1) Is there a real table at all? (2) If so, what kind of object can it be? Both Berkeley and Leibniz accept that there is a real table. But Berkeley says the table consists of certain ideas in the mind of God. Leibniz says the table is a colony of souls. So both philosophers answer yes to our first question. They differ from ordinary people only in their answer to our second question. In fact, almost all philosophers seem to agree that there is a real table. Almost all agree that our sense-data (colour, shape, smoothness, etc.) may depend on us, however much that dependence varies. Yet the occurrence of these sense-data signals something that exists independently of us. This independent thing may differ completely from our sense-data. Still, we should regard it as causing those sense-data whenever we are in a suitable relation to the real table.

Now obviously this point in which the philosophers are agreed—the view that there is a real table, whatever its nature may be—is vitally important, and it will be worth while to consider what reasons there are for accepting this view before we go on to the further question as to the nature of the real table. Our next chapter, therefore, will be concerned with the reasons for supposing that there is a real table at all.

Clearly, the point on which the philosophers agree is vitally important. They agree that there is a real table, whatever its nature may be. Before asking about the real table’s nature, it is worth considering the reasons for accepting its existence. Our next chapter, therefore, will examine the reasons for supposing that a real table exists at all.

Before we go farther it will be well to consider for a moment what it is that we have discovered so far. It has appeared that, if we take any common object of the sort that is supposed to be known by the senses, what the senses immediately tell us is not the truth about the object as it is apart from us, but only the truth about certain sense-data which, so far as we can see, depend upon the relations between us and the object. Thus what we directly see and feel is merely 'appearance', which we believe to be a sign of some 'reality' behind. But if the reality is not what appears, have we any means of knowing whether there is any reality at all? And if so, have we any means of finding out what it is like?

Before we go further, we should briefly consider what we have discovered so far. Consider any ordinary object of the kind we suppose we know through our senses. It seems that our senses do not immediately tell us the truth about the object as it exists independently of us. Instead, our senses tell us only the truth about certain sense-data. As far as we can tell, these sense-data depend on the relationship between us and the object. So what we directly see and feel is merely 'appearance', which we believe points to some 'reality' behind it. But if reality is not what appears, do we have any way of knowing whether any reality exists at all? And if so, do we have any way of finding out what that reality is like?

Such questions are bewildering, and it is difficult to know that even the strangest hypotheses may not be true. Thus our familiar table, which has roused but the slightest thoughts in us hitherto, has become a problem full of surprising possibilities. The one thing we know about it is that it is not what it seems. Beyond this modest result, so far, we have the most complete liberty of conjecture. Leibniz tells us it is a community of souls: Berkeley tells us it is an idea in the mind of God; sober science, scarcely less wonderful, tells us it is a vast collection of electric charges in violent motion.

Such questions are bewildering, and it is hard to rule out even the strangest possibilities. Until now, our familiar table has barely given us anything to think about. Now the table has become a problem full of surprising possibilities. The one thing we know about the table is that it is not what it seems. Beyond this modest conclusion, we are so far completely free to speculate. Leibniz tells us the table is a community of souls. Berkeley tells us the table is an idea in the mind of God. Sober science tells us something almost as remarkable: the table is a vast collection of electric charges moving violently.

Among these surprising possibilities, doubt suggests that perhaps there is no table at all. Philosophy, if it cannot answer so many questions as we could wish, has at least the power of asking questions which increase the interest of the world, and show the strangeness and wonder lying just below the surface even in the commonest things of daily life.

Among these surprising possibilities, doubt suggests that perhaps there is no table at all. If philosophy cannot answer as many questions as we would like, it can at least ask questions. These questions make the world more interesting. They also reveal the strangeness and wonder just below the surface of even the most ordinary things in daily life.