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.
I can, in fact, imagine that some of those who would call this thing a
sensation would deny that my judgment is _about_ it at all. It would
sometimes be spoken of as the sensation which mediates my perception
of this inkstand in this instance. And I can imagine that some of
those who would so speak of it might be inclined to say that when
I judge "This is an inkstand," my judgment is about this inkstand
which I perceive, and not, in any sense at all, about the sensation
which mediates my perception of it. They may perhaps imagine that the
sensation mediates my perception of the inkstand only in the sense
that it brings the inkstand before my mind in such a way that, once it
is before my mind, I can make a judgment about it, which is _not_ a
judgment about the mediating sensation at all; and that such a judgment
is the one I am actually expressing when I say "This is an inkstand."
Such a view, if it is held, seems to me to be quite certainly false,
and is what I have intended to deny. And perhaps I can put most clearly
the reason why it seems to me false, by saying that, if (which may
be doubted) there is anything which is this inkstand, that thing is
certainly not given to me independently of this sense-datum, in such
a sense that I can possibly make a judgment about it which is _not_
a judgment about this sense-datum. I am not, of course, denying that
I do perceive this inkstand, and that my judgment is, in a sense, a
judgment about it. Both these things seem to me to be quite obviously
true. I am only maintaining that my judgment is _also,_ in another
sense, a judgment about this sense-datum which mediates my perception
of the inkstand. Those who say that this sense-datum does mediate my
perception of the inkstand, would, of course, admit that my perception
of the inkstand is, in a sense, dependent upon the sense-datum; that
it is dependent is implied in the mere statement that it is mediated
by it. But it might be maintained that it is dependent on it only in
the sense in which, when the idea of one object is called up in my
mind, through association, by the idea of another, the idea which is
called up is dependent on the idea which calls it up. What I wish to
maintain, and what seems to me to be quite certainly true, is that my
perception of this inkstand is dependent on this sense-datum, in a
quite different and far more intimate sense than this. It is dependent
on it in the sense that, if there is anything which is this inkstand,
then, in perceiving that thing, I am knowing it _only_ as _the_ thing
which stands in a certain relation to this sense-datum. When the idea
of one object is called up in my mind by the idea of another, I do
not know the second object _only_ as _the_ thing which has a certain
relation to the first: on the contrary, I can make a judgment about the
second object, which is not a judgment about the first. And similarly
in the case of two sense-data which are presented to me simultaneously,
I do not know the one _only_ as a thing which has a certain relation to
the other. But in the case of this sense-datum and this inkstand the
case seems to me to be plainly quite different. If there be a thing
which is this inkstand at all, it is certainly _only_ known to me as
_the_ thing which stands in a certain relation to this sense-datum. It
is not given to me, in the sense in which this sense-datum is given.
If there be such a thing at all, it is quite certainly only known to
me by description, in the sense in which Mr. Russell uses that phrase;
and the description by which it is known is that of being _the_ thing
which stands to this sense-datum in a certain relation. That is to
say, when I make such a judgment as "This inkstand is a good big one";
what I am really judging is: "There is a thing which stands to _this_
in a certain relation, and which is an inkstand, and that thing is
a good big one"--where "_this_" stands for this presented object. I
am referring to or identifying the thing which is this inkstand, if
there be such a thing at all, only as the thing which stands to this
sense-datum in a certain relation; and hence my judgment, though in
one sense it may be said to be a judgment about the inkstand, is quite
certainly also, in another sense, a judgment about this sense-datum.
This seems to me so clear, that I wonder how anyone can deny it; and
perhaps nobody would. But I cannot help thinking that it is not clear
to everybody; partly because, so far as I can make out, nobody before
Mr. Russell had pointed out the extreme difference there is between a
judgment about a thing known only by description to the individual who
makes the judgment, and a judgment about a thing not known to him only
in this way; and partly because so many people seem still utterly to
have failed to understand what the distinction is which he expresses in
this way. I will try to make the point clear, in a slightly different
way. Suppose I am seeing two coins, lying side by side, and am not
perceiving them in any other way except by sight. It will be plain to
everybody, I think, that, when I identify the one as "This one" and
the other as "That one," I identify them only by reference to the two
visual presented objects, which correspond respectively to the one and
to the other. But what may not, I think, be realised, is that the sense
in which I identify them by reference to the corresponding sense-data,
is one which involves that every judgment which I make about the one
is a judgment about the sense-datum which corresponds to it, and every
judgment I make about the other, a judgment about the sense-datum which
corresponds to _it_: I simply cannot make a judgment about either,
which is not a judgment about the corresponding sense-datum. But if the
two coins were given to me, in the sense in which the two sense-data
are, this would certainly not be the case. I can identify and
distinguish the two sense-data _directly,_ this as this one, and that
as that one: I do not need to identify either as _the_ thing which has
this relation to this other thing. But I certainly cannot thus directly
identify the two coins. I have not four things presented to me (1)
_this_ sense-datum, (2) _that_ sense-datum, (3) _this_ coin, and (4)
_that_ coin, but two only_--this_ sense-datum and _that_ sense-datum.
When, therefore, I judge "_This_ is a coin," my judgment is certainly
a judgment about the one sense-datum, and when I judge "And _that_
is also a coin," it is certainly a judgment about the other. Only,
in spite of what my language might seem to imply, I am certainly not
judging either of the one sense-datum that it is a whole coin, nor yet
of the other that it is one.
This, then, seems to me fundamentally certain about judgments of this
kind. Whenever we make such a judgment we can easily pick out an object
(whether we call it a sensation or a sense-datum, or not), which is,
in an easily intelligible sense, _the_ object which is the real or
ultimate subject of our judgment; and yet, in many cases at all events,
what we are judging with regard to this object is certainly not that it
is an object of the kind, for which the term which appears to express
the predicate of our judgment is a name.
But if this be so, what is it that I am judging, in all such cases,
about the presented object, which is the real or ultimate subject of my
judgment? It is at this point that we come to questions which seem to
me to be really uncertain and difficult to answer.
To begin with, there is one answer which is naturally suggested by the
reason I have given for saying that, in this case, it is quite obvious
that I am not judging, with regard to this presented object, that
_it_ is an inkstand, whereas it is not in the same way, quite obvious
that, in making such a judgment as "This is a soap-bubble" or "This is
a drop of water," I may not be judging, of the object about which my
judgment is, that that very object really is a soap-bubble or a drop
of water. The reason I gave is that it is quite obvious that I do not
take this presented object to be a _whole_ inkstand: that, at most, I
only take it to be part of the surface of an inkstand. And this reason
naturally suggests that the true answer to our question may be that
what I am judging of the presented object is just that it is a part of
the surface of an inkstand. This answer seems to me to be obviously on
quite a different level from the suggestion that I am judging it really
to be an inkstand. It is not childishly obvious that I am not judging
it to be part of the surface of an inkstand, as it is that I am not
judging it to be an inkstand--a whole one.
On this view, when I say such things as "That is an inkstand," "That
is a door," "This is a coin," these expressions would really only be
a loose way of saying "That is part of the surface of an inkstand,"
"That is part of the surface of a door," "This is part of the surface
of a coin." And there would, I think, plainly be nothing surprising
in the fact that we should use language thus loosely. What, at first
sight, appears to be a paradox, namely that, whereas I appear to be
asserting of a given thing that it is of a certain kind, I am not
really asserting of the thing in question that it is of that kind at
all, would be susceptible of an easy explanation. And moreover, if
this view were true, it would offer an excellent illustration of the
difference between a thing known only by description and a thing not so
known, and would show how entirely free from mystery that distinction
is. On this view, when I judge "That inkstand is a good big one" I
shall in effect be judging: "There is one and only one inkstand of
which _this_ is part of the surface, and the inkstand of which this is
true is a good big one." It would be quite clear that the part of the
surface of the inkstand was given to me in a sense in which the whole
was not, just as it is in fact clear that I do now _"see"_ this part
of the surface of this inkstand, in a sense in which I do _not_ "see"
the whole; and that my judgment, while it is, in fact, _about_ both the
whole inkstand, and also _about_ one particular part of its surface, is
_about_ them in two entirely different senses.
This view is one, which it is at first sight, I think, very natural to
suppose to be true. But before giving the reasons, why, nevertheless,
it seems to me extremely doubtful, I think it is desirable to try
to explain more precisely what I mean by it. The word "part" is one
which is often used extremely vaguely in philosophy; and I can imagine
that some people would be willing to assent to the proposition that
this sense-datum really is, in some sense or other, a "part" of this
inkstand, and that what I am judging with regard to it, when I
judge "This is an inkstand," is, in effect, "There is an inkstand,
of which _this_ is a part," who would be far from allowing that this
can possibly be what I am judging, when once they understand what the
sense is in which I am here using the word "part." What this sense
is, I am quite unable to define; but I hope I may be able to make my
meaning sufficiently clear, by giving instances of things which are
undoubtedly "parts" of other things in the sense in question. There is,
it seems to me, a sense of the word "part," in which we all constantly
use the word with perfect precision, and, which, therefore, we all
understand very well, however little we may be able to define it. It is
the sense in which the trunk of any tree is undoubtedly a part of that
tree; in which this finger of mine is undoubtedly a part of my hand,
and my hand a part of my body. This is a sense in which every part
of a material thing or physical object is itself a material thing or
physical object; and it is, so far as I can see, the only proper sense
in which a material thing can be said to have parts. The view which I
wish to discuss is the view that I am judging this presented object to
be a part of an inkstand, in this sense. And the nature of the view
can perhaps be brought out more clearly, by mentioning one important
corollary which would follow from it. I am, of course, at this moment,
seeing many parts of the surface of this inkstand. But all these
parts, except one, are, in fact, themselves parts of that one. That
one is the one of which we should naturally speak as "_the_ part of
the surface that I am now seeing" or as "_this_ part of the surface of
this inkstand." There is only one part of the surface of this inkstand,
which does thus contain, as parts, all the other parts that I am now
seeing. And, if it were true that I am judging this presented object to
be a part of the surface of an inkstand at all, in the sense I mean,
it would follow that this presented object must, if my judgment "This
is an inkstand" be true (as it certainly is), be identical with this
part, which contains all the other parts which I am seeing; since there
is plainly no other part with which it could possibly be identified.
That is to say, if I am really judging of this presented object that it
is part of the surface of an inkstand, in the sense I mean, it must be
the case that everything which is true of what I should call "this part
of the surface of this inkstand" is, in fact, true of this presented
object.
This view, therefore, that what we are judging of the ultimate subject
of our judgment, when we judge "This is a so-and-so," is, in general,
merely that the subject in question is a _part_ of a thing of the
kind in question, can, I think, be most clearly discussed, by asking
whether, in this case, this presented object can really be identical
with this part of the surface of this inkstand. If it can't, then most
certainly I am not judging of it that it is a part of the surface of an
inkstand at all. For my judgment, whatever it is, is true. And yet, if
this presented object is not identical with this part of the surface of
this inkstand, it certainly is not a part of an inkstand at all; since
there is no other part, either of this inkstand or of any other, with
which it could possibly be supposed to be identical.
Can we, then, hold that this sense-datum really is identical with this
part of the surface of this inkstand? That everything which is true of
the one is true of the other?
An enormous number of very familiar arguments have been used by various
philosophers, which, if they were sound, would show that we can not.
Some of these arguments seem to me to be quite clearly not sound--all,
for instance, which rest either on the assumption that this sense-datum
can only exist so long as it is perceived, or on the assumption that
it can only exist so long as it is perceived _by me._ Of others I
suspect that they may have some force, though I am quite unable to see
that they have any. Such, for instance, are all those which assume
either that this sense-datum is a sensation or feeling of mine, in a
sense which includes the assertion that it is dependent on my mind
in the very same sense in which my perception of it obviously is so;
or that it is causally dependent on my body in the sense in which my
perception of it admittedly is so. But others do seem to me to have
great force. I will, however, confine myself to trying to state one,
which seems to me to have as much as any. It will be found that this
one involves an assumption, which does seem to me to have great force,
but which yet seems to me to be doubtful. So far as I know, all good
arguments against the view that this sense-datum really is identical
with this part of the surface of the inkstand, do involve this same
assumption, and have no more force than it has. But in this, of course,
I may be wrong. Perhaps some one will be able to point out an argument,
which is obviously quite independent of it, and which yet has force.
The argument I mean involves considerations which are exceedingly
familiar, so familiar that I am afraid every one may be sick of
hearing them alluded to. But, in spite of this fact, it seems to
me not quite easy to put it quite precisely, in a way which will
distinguish it clearly from other arguments involving the same familiar
considerations, but which do not seem to me to be equally cogent. I
want, therefore, to try to put it with a degree of precision, which
will prevent irrelevant objections from being made to it--objections
which would, I think, be relevant against some of these other
arguments, but are not, I think, relevant against it.
The fact is that we all, exceedingly commonly, when, at each of two
times, separated by a longer or shorter interval, we see a part of the
surface of a material thing, in the sense in which I am now seeing
this part of the surface of this inkstand, or when at one time we see
such a surface and at another perceive one by touch, make, on the
second occasion, the judgment "_This_ part of a surface is the _same_
part of the surface of the same thing, as that which I was seeing
(or perceiving by touch) just now." How commonly we all do this can
scarcely be exaggerated. I look at this inkstand, and then I look
again, and on the second occasion I judge "This part of the surface
of this inkstand is the same as, or at least contains a part which is
the same as a part of, the part of its surface which I was seeing just
now." Or I look at this finger and then I touch it, and I judge, on the
second occasion, "This part of the surface of this finger is the same
as one of those I was seeing just now." We all thus constantly identify
a part of a surface of a material thing which we are perceiving at one
time with a part which we _were_ perceiving at another.
Now, when we do this--when we judge "This is the _same_ part of the
same thing as I was seeing or touching just now," we, of course, do
not mean to exclude the possibility that the part in question may
have changed during the interval; that it is really different, on the
second occasion, either in shape or size or quality, or in all three,
from what it was on the first. That is to say, the sense of sameness
which we are here concerned with is one which clearly does not exclude
change. We may even be prepared to assert, on general grounds, in all
such cases, that the surface in question certainly must have changed.
But nevertheless there is a great difference in one respect, between
two kinds of such cases, both of which occur exceedingly commonly.
If I watch somebody blowing air into a child's balloon, it constantly
happens, at certain stages in the process, that I judge with regard
to the part of the surface which I am seeing at that stage, not only
that it _is_ larger than it was at an earlier stage, but that it is
_perceptibly_ larger. Or, if I pull the face of an india-rubber doll,
I may judge at a certain stage in the process that the patch of red
colour on its cheek not only is different in shape from what it was
at the beginning, but is _perceptibly_ so; it may, for instance, be a
perceptibly flatter ellipse than it was to start with. Or, if I watch
a person blushing, I may judge at a certain stage that a certain part
of the surface of his face not only is different in colour from what
it was, when I saw it before he began to blush, but is _perceptibly_
so--perceptibly redder. In enormous numbers of cases we do thus judge
of a surface seen at a given time that it is thus _perceptibly_
different in size, or in shape, or in colour, from what it was when we
saw it before. But cases are at least equally numerous in which, though
we might, on general grounds be prepared to assert that it _must_ have
changed in some respect, we should not be prepared to assert that it
had, in any respect whatever, changed _perceptibly._ Of this part
of this surface of this inkstand, for instance, I am certainly not
prepared to assert that it is now perceptibly different in any respect
from what it was when I saw it just now. And similar cases are so
numerous that I need not give further instances. We can, therefore,
divide cases, in which we judge, of a part of a surface which we are
seeing, "This is the same part of the surface of the same material
thing as the one I saw just now," into cases where we should also judge
"But it is perceptibly different from what it was then," and cases in
which, even though we might assert "It _must_ be different," we are
certainly not prepared to assert that it is _perceptibly_ so.
But now let us consider the cases in which we are not prepared to
assert that the surface in question has changed perceptibly. The
strange fact, from which the argument I mean is drawn, is that, in a
very large number of such cases, it seems as if it were unmistakably
true that the presented object, about which we are making our judgment
when we talk of "This surface" at the later time, _is_ perceptibly
different, from that about which we are making it when we talk of the
surface I saw just now. If, at the later time, I am at a sufficiently
greater distance from the surface, the presented object which
corresponds to it at the time seems to be perceptibly smaller, than
the one which corresponded to it before. If I am looking at it from
a sufficiently oblique angle, the later presented object often seems
to be perceptibly different in shape--a perceptibly flatter ellipse,
for instance. If I am looking at it, with blue spectacles on, when
formerly I had none, the later presented object seems to be perceptibly
different in colour from the earlier one. If I am perceiving it by
touch alone, whereas formerly I was perceiving it by sight alone,
the later presented object seems to be perceptibly different from
the earlier, in respect of the fact that it is not coloured at all,
whereas the earlier was, and that, on the other hand, it has certain
tactual qualities, which the earlier had not got. All this seems to
be as plain as it can be, and yet it makes absolutely no difference
to the fact that of the surface in question we are _not_ prepared to
judge that it is perceptibly different from what it was. Sometimes,
of course, where there seems to be no doubt that the later presented
object is perceptibly different from the earlier, we may not notice
that it is so. But even where we do notice the apparent difference, we
do still continue to judge of the surface in question: This surface
is not, so far as I can tell with certainty by perception, in any way
different from what it was when I saw it or touched it just now; I am
_not_ prepared to assert that it has changed perceptibly. It seems,
therefore, to be absolutely impossible that the surface seen at the
later time should be identical with the object presented then, and the
surface seen at the earlier identical with the object presented then,
for the simple reason that, whereas with regard to the later seen
surface I am not prepared to judge that it is in any way perceptibly
different from that seen earlier, it seems that with regard to the
later sense-datum I cannot fail to judge that it _is_ perceptibly
different from the earlier one: the fact that they are perceptibly
different simply stares me in the face. It seems, in short, that when,
in such a case, I judge: "This surface is not, so far as I can tell,
perceptibly different from the one I saw just now," I cannot possibly
be judging of the presented object "_This_ is not, so far as I can
tell, perceptibly different from that object which was presented to
me just now," for the simple reason that I _can_ tell, as certainly,
almost, as I can tell anything, that it is perceptibly different.
That is the argument, as well as I can put it, for saying that this
presented object, is _not_ identical with this part of the surface of
this inkstand; and that, therefore, when I judge "This is part of the
surface of an inkstand," I am not judging of this presented object,
which nevertheless is the ultimate subject of my judgment, that _it_ is
part of the surface of an inkstand. And this argument does seem to me
to be a very powerful one.
But nevertheless it does not seem to me to be quite conclusive, because
it rests on an assumption, which, though it seems to me to have great
force, does not seem to me quite certain. The assumption I mean is the
assumption that, in such cases as those I have spoken of, the later
presented object really is perceptibly different from the earlier. This
assumption has, if I am not mistaken, seemed to many philosophers to
be quite unquestionable; they have never even thought of questioning
it; and I own that it used to be so with me. And I am still not sure
that I may not be talking sheer nonsense in suggesting that it can
be questioned. But, if I am, I am no longer able to see that I am.
What now seems to me to be possible is that the sense-datum which
corresponds to a tree, which I am seeing, when I am a mile off, may not
really be perceived to _be_ smaller than the one, which corresponds
to the same tree, when I see it from a distance of only a hundred
yards, but that it is only perceived to _seem_ smaller; that the
sense-datum which corresponds to a penny, which I am seeing obliquely,
is not really perceived to _be_ different in shape from that which
corresponded to the penny, when I was straight in front of it, but is
only perceived to _seem_ different--that all that is perceived is that
the one _seems_ elliptical and the other circular; that the sense-datum
presented to me when I have the blue spectacles on is not perceived
to _be_ different in colour from the one presented to me when I have
not, but only to _seem_ so; and finally that the sense-datum presented
when I touch this finger is not perceived to _be_ different in any way
from that presented to me when I see it, but only to _seem_ so that
I do not perceive the one to be coloured and the other not to be so,
but only that the one _seems_ coloured and the other not. If such a
view is to be possible, we shall have, of course, to maintain that
the kind of experience which I have expressed by saying one _seems_
different from the other_--"seems_ circular," _"seems_ blue," _"seems_
coloured," and so on--involves an ultimate, not further analysable,
kind of psychological relation, not to be identified either with that
involved in being "perceived" to be so and so, or with that involved
in being "judged" to be so and so; since a presented object might, in
this sense, _seem_ to be elliptical, _seem_ to be blue, etc., when it
is neither perceived to be so, nor judged to be so. But there seems to
me to be no reason why there should not be such an ultimate relation.
The great objection to such a view seems to me to be the difficulty of
believing that I don't actually perceive this sense-datum to _be_ red,
for instance, and that other to _be_ elliptical; that I only perceive,
in many cases, that it _seems_ so. I cannot, however, now persuade
myself that it is quite clear that I do perceive it to _be_ so. And,
if I don't, then it seems really possible that this presented object
really is identical with this part of the surface of this inkstand;
since, when I judge, as in the cases supposed, that the surface in
question is _not_, so far as I can tell, perceptibly different from
what it was, I might really be judging of the two sense-data that they
also were not, so far as I can tell, perceptibly different, the only
difference between the two that _is_ perceptible, being that the one
_seems_ to be of a certain size, shape or colour, and the other to
be of a different and incompatible size, shape or colour. Of course,
in those cases, as in that of the balloon being blown up, where I
"perceive" that the surface has changed, _e.g._ in size, it would have
to be admitted that I do perceive of the two sense-data not merely that
they _seem_ different in size, but that they _are_ so. But I think it
would be possible to maintain that the sense in which, in these cases,
I "perceive" them to _be_ different, is a different one from that in
which, both in these and in the others, I perceive them to _seem_ so.
Possibly in making this suggestion that sense-data, in cases where most
philosophers have assumed unhesitatingly that they are _perceived_ to
be different, are only really perceived to _seem_ different, I am, as I
said, talking sheer nonsense, though I cannot, at the moment, see that
I am. And possibly, even if this suggestion itself is not nonsense,
even if it is true, there may be other fatal objections to the view
that this presented object really is identical with this part of the
surface of this inkstand. But what seems to me certain is that, unless
this suggestion is true, then this presented object is certainly _not_
identical with this part of the surface of this inkstand. And since it
is doubtful whether it is not nonsense, and still more doubtful whether
it is true, it must, I think, be admitted to be highly doubtful whether
the two _are_ identical. But, if they are not identical, then what I am
judging with regard to this presented object, when I judge "This is an
inkstand," is certainly _not_ that it is itself part of the surface of
an inkstand; and hence, it is worth while to inquire further, what, if
I am not judging this, I _can_ be judging with regard to it.
And here, I think, the first natural suggestion to make is that just
as, when I talk of "this inkstand," what I seem really to mean is
"_the_ inkstand of which _this_ is part of the surface," so that the
inkstand is only known to me by description as the inkstand of which
this material surface is part of the surface, so again when I talk of
"this material surface," what I really mean is "_the_ material surface
to which _this_ (presented object) has a certain relation," so that
this surface is, in its turn, only known to me by description as _the_
surface which has a certain relation to this presented object. If that
were so, then what I should be judging of this presented object, when I
judge "This is part of the surface of an inkstand," would be not that
it is itself such a part, but that _the_ thing which stands to it in
a certain relation is such a part: in short, what I should be judging
with regard to _it,_ would be "There's one thing and one only which
stands to _this_ in _this_ relation, and the thing which does so is
part of the surface of an inkstand."
But if we are to adopt the view that something of this sort is what we
are judging, there occurs at once the pressing question: What on earth
can the relation be with regard to which we are judging, that one and
only one thing stands in it to this presented object? And this is a
question to which, so far as I know, none of those philosophers, who
_both_ hold (as many do) that this presented object is _not_ identical
with this part of the surface of this inkstand, _and_ also that there
really is something of which it could be truly predicated that it is
this part of the surface of this inkstand (that is to say, who reject
all views of the Mill-Russell type), have given anything like a clear
answer. It does not seem to have occurred to them that it requires an
answer, chiefly, I think, because it has not occurred to them to ask
what we can be judging when we make judgments of this sort. There are
only two answers, that I can think of, which might be suggested with
any plausibility.
Many philosophers, who take the view that the presented objects about
which we make these judgments are sensations of ours, and some even who
do not, are in the habit of talking of _"the_ causes" of these objects
as if we knew, in the case of each, that it had one and only one cause;
and many of them seem to think that this part of the surface of this
inkstand could be correctly described as _the_ cause of this presented
object. They suggest, therefore, the view that what I am judging in
this case might be: "This presented object has one and only one cause,
and that cause is part of the surface of an inkstand." It seems to me
quite obvious that _this_ view, at all events, is utterly untenable. I
do not believe for a moment, nor does any one, and certainly therefore
do not judge, that this presented object has _only_ one cause: I
believe that it has a whole series of different causes. I do, in fact,
believe that this part of the surface of this inkstand is _one_ among
the causes of my perception of this presented object: that seems to
me to be a very well established scientific proposition. And I am
prepared to admit that there _may_ be good reasons for thinking that
it is one among the causes of this presented object itself, though I
cannot myself see that there are any. But that it is the _only_ cause
of this presented object I certainly do not believe, nor, I think,
does anybody, and hence my judgment certainly cannot be "_The_ cause
of this is part of the surface of an inkstand." It might no doubt, be
possible to define some _kind_ of causal relation, such that it might
be plausibly held that it and it alone causes this presented object _in
that particular way._ But any such definition would, so far as I can
see, be necessarily very complicated. And, even when we have got it,
it seems to me it would be highly improbable we could truly say that
what we are judging in these cases is: "This presented object has one
and only one cause, of this special kind." Still, I do not wish to deny
that some such view may _possibly_ be true.
The only other suggestion I can make is that there may be some
ultimate, not further definable relation, which we might for instance,
call the relation of "being a manifestation of," such that we might
conceivably be judging: "There is one and only one thing of which this
presented object is a manifestation, and _that_ thing is part of the
surface of an inkstand." And here again, it seems to me just possible
that this _may_ be a true account of what we are judging; only I cannot
find the slightest sign that I am in fact aware of any such relation.
Possibly other suggestions could be made as to what the relation is,
with regard to which it could be plausibly supposed that in all cases,
where we make these judgments we are in fact judging of the presented
object "There is one and only one thing which stands to this object in
_this_ relation." But it seems to me at least very doubtful whether
there is any such relation at all; whether, therefore, our judgment
really is of this form, and whether therefore, this part of the surface
of this inkstand really is known to me by description as _the_ thing
which stands in a certain relation to this presented object. But if it
isn't, and if, also, we cannot take the view that what I am judging
is that this presented object _itself_ is a part of the surface of an
inkstand, there would seem to be no possible alternative but that we
must take some view of what I have called the Mill-Russell type. Views
of this type, if I understand them rightly, are distinguished from
those which I have hitherto considered, by the fact that, according to
them, there is nothing whatever in the Universe of which it could truly
be predicated that it is this part of the surface of this inkstand,
or indeed that it is _a_ part of the surface of an inkstand, or an
inkstand, at all. They hold, in short, that though there are plenty of
material things in the Universe, there is nothing in it of which it
could truly be asserted that _it_ is a material thing: that, though,
when I assert "This is an inkstand," my assertion is true, and is such
that it follows from it that there is in the Universe at least one
inkstand, and, therefore, at least one material thing, yet it does not
follow from it that there is anything which is a material thing. When
I judge "This is an inkstand," I am judging this presented object to
possess a certain property, which is such that, if there are things,
which possess that property, there are inkstands and material things,
but which is such that nothing which possesses it is itself a material
thing; so that in judging that there are material things, we are really
always judging of some _other_ property, which is not that of being a
material thing, that there are things which possess _it._ It seems to
me quite possible, of course, that some view of this type is the true
one. Indeed, this paper may be regarded, if you like, as an argument in
favour of the proposition that some such view _must_ be true. Certainly
one of my main objects in writing it was to put as plainly as I can
some grave difficulties which seem to me to stand in the way of any
other view; in the hope that some of those, who reject all views of
the Mill-Russell type, may explain clearly which of the alternatives
I have suggested they would adopt, or whether, perhaps, some other
which has not occurred to me. It does not seem to me to be always
sufficiently realised how difficult it is to find _any_ answer to my
question "What are we judging in these cases?" to which there are not
very grave objections, unless we adopt an answer of the Mill-Russell
type. That an answer of this type _is_ the true one, I am not myself,
in spite of these objections, by any means convinced. The truth is I am
completely puzzled as to what the true answer can be. At the present
moment, I am rather inclined to favour the view that what I am judging
of this presented object is that it is itself a part of the surface of
an inkstand--that, therefore, it really is identical with this part of
the surface of this inkstand, in spite of the fact that this involves
the view that, where, hitherto, I have always supposed myself to be
perceiving of two presented objects that they really were different, I
was, in fact, only perceiving that they _seemed_ to be different. But,
as I have said, it seems to me quite possible that this view is, as I
have hitherto supposed, sheer nonsense; and, in any case, there are, no
doubt, other serious objections to the view that this presented object
is this part of the surface of this inkstand.