IDEALISM
The word 'idealism' is used by different philosophers in somewhat
different senses. We shall understand by it the doctrine that
whatever exists, or at any rate whatever can be known to exist, must
be in some sense mental. This doctrine, which is very widely held
among philosophers, has several forms, and is advocated on several
different grounds. The doctrine is so widely held, and so interesting
in itself, that even the briefest survey of philosophy must give some
account of it.
Those who are unaccustomed to philosophical speculation may be
inclined to dismiss such a doctrine as obviously absurd. There is no
doubt that common sense regards tables and chairs and the sun and moon
and material objects generally as something radically different from
minds and the contents of minds, and as having an existence which
might continue if minds ceased. We think of matter as having existed
long before there were any minds, and it is hard to think of it as a
mere product of mental activity. But whether true or false, idealism
is not to be dismissed as obviously absurd.
We have seen that, even if physical objects do have an independent
existence, they must differ very widely from sense-data, and can only
have a _correspondence_ with sense-data, in the same sort of way in
which a catalogue has a correspondence with the things catalogued.
Hence common sense leaves us completely in the dark as to the true
intrinsic nature of physical objects, and if there were good reason to
regard them as mental, we could not legitimately reject this opinion
merely because it strikes us as strange. The truth about physical
objects _must_ be strange. It may be unattainable, but if any
philosopher believes that he has attained it, the fact that what he
offers as the truth is strange ought not to be made a ground of
objection to his opinion.
The grounds on which idealism is advocated are generally grounds
derived from the theory of knowledge, that is to say, from a
discussion of the conditions which things must satisfy in order that
we may be able to know them. The first serious attempt to establish
idealism on such grounds was that of Bishop Berkeley. He proved
first, by arguments which were largely valid, that our sense-data
cannot be supposed to have an existence independent of us, but must
be, in part at least, 'in' the mind, in the sense that their existence
would not continue if there were no seeing or hearing or touching or
smelling or tasting. So far, his contention was almost certainly
valid, even if some of his arguments were not so. But he went on to
argue that sense-data were the only things of whose existence our
perceptions could assure us; and that to be known is to be 'in' a
mind, and therefore to be mental. Hence he concluded that nothing can
ever be known except what is in some mind, and that whatever is known
without being in my mind must be in some other mind.
In order to understand his argument, it is necessary to understand his
use of the word 'idea'. He gives the name 'idea' to anything which is
_immediately_ known, as, for example, sense-data are known. Thus a
particular colour which we see is an idea; so is a voice which we
hear, and so on. But the term is not wholly confined to sense-data.
There will also be things remembered or imagined, for with such things
also we have immediate acquaintance at the moment of remembering or
imagining. All such immediate data he calls 'ideas'.
He then proceeds to consider common objects, such as a tree, for
instance. He shows that all we know immediately when we 'perceive'
the tree consists of ideas in his sense of the word, and he argues
that there is not the slightest ground for supposing that there is
anything real about the tree except what is perceived. Its being, he
says, consists in being perceived: in the Latin of the schoolmen its
'_esse_' is '_percipi_'. He fully admits that the tree must continue
to exist even when we shut our eyes or when no human being is near it.
But this continued existence, he says, is due to the fact that God
continues to perceive it; the 'real' tree, which corresponds to what
we called the physical object, consists of ideas in the mind of God,
ideas more or less like those we have when we see the tree, but
differing in the fact that they are permanent in God's mind so long as
the tree continues to exist. All our perceptions, according to him,
consist in a partial participation in God's perceptions, and it is
because of this participation that different people see more or less
the same tree. Thus apart from minds and their ideas there is nothing
in the world, nor is it possible that anything else should ever be
known, since whatever is known is necessarily an idea.
There are in this argument a good many fallacies which have been
important in the history of philosophy, and which it will be as well
to bring to light. In the first place, there is a confusion
engendered by the use of the word 'idea'. We think of an idea as
essentially something in somebody's mind, and thus when we are told
that a tree consists entirely of ideas, it is natural to suppose that,
if so, the tree must be entirely in minds. But the notion of being
'in' the mind is ambiguous. We speak of bearing a person in mind, not
meaning that the person is in our minds, but that a thought of him is
in our minds. When a man says that some business he had to arrange
went clean out of his mind, he does not mean to imply that the
business itself was ever in his mind, but only that a thought of the
business was formerly in his mind, but afterwards ceased to be in his
mind. And so when Berkeley says that the tree must be in our minds if
we can know it, all that he really has a right to say is that a
thought of the tree must be in our minds. To argue that the tree
itself must be in our minds is like arguing that a person whom we bear
in mind is himself in our minds. This confusion may seem too gross to
have been really committed by any competent philosopher, but various
attendant circumstances rendered it possible. In order to see how it
was possible, we must go more deeply into the question as to the
nature of ideas.
Before taking up the general question of the nature of ideas, we must
disentangle two entirely separate questions which arise concerning
sense-data and physical objects. We saw that, for various reasons of
detail, Berkeley was right in treating the sense-data which constitute
our perception of the tree as more or less subjective, in the sense
that they depend upon us as much as upon the tree, and would not exist
if the tree were not being perceived. But this is an entirely
different point from the one by which Berkeley seeks to prove that
whatever can be immediately known must be in a mind. For this purpose
arguments of detail as to the dependence of sense-data upon us are
useless. It is necessary to prove, generally, that by being known,
things are shown to be mental. This is what Berkeley believes himself
to have done. It is this question, and not our previous question as
to the difference between sense-data and the physical object, that
must now concern us.
Taking the word 'idea' in Berkeley's sense, there are two quite
distinct things to be considered whenever an idea is before the mind.
There is on the one hand the thing of which we are aware--say the
colour of my table--and on the other hand the actual awareness itself,
the mental act of apprehending the thing. The mental act is
undoubtedly mental, but is there any reason to suppose that the thing
apprehended is in any sense mental? Our previous arguments concerning
the colour did not prove it to be mental; they only proved that its
existence depends upon the relation of our sense organs to the
physical object--in our case, the table. That is to say, they proved
that a certain colour will exist, in a certain light, if a normal eye
is placed at a certain point relatively to the table. They did not
prove that the colour is in the mind of the percipient.
Berkeley's view, that obviously the colour must be in the mind, seems
to depend for its plausibility upon confusing the thing apprehended
with the act of apprehension. Either of these might be called an
'idea'; probably either would have been called an idea by Berkeley.
The act is undoubtedly in the mind; hence, when we are thinking of the
act, we readily assent to the view that ideas must be in the mind.
Then, forgetting that this was only true when ideas were taken as acts
of apprehension, we transfer the proposition that 'ideas are in the
mind' to ideas in the other sense, i.e. to the things apprehended by
our acts of apprehension. Thus, by an unconscious equivocation, we
arrive at the conclusion that whatever we can apprehend must be in our
minds. This seems to be the true analysis of Berkeley's argument, and
the ultimate fallacy upon which it rests.
This question of the distinction between act and object in our
apprehending of things is vitally important, since our whole power of
acquiring knowledge is bound up with it. The faculty of being
acquainted with things other than itself is the main characteristic of
a mind. Acquaintance with objects essentially consists in a relation
between the mind and something other than the mind; it is this that
constitutes the mind's power of knowing things. If we say that the
things known must be in the mind, we are either unduly limiting the
mind's power of knowing, or we are uttering a mere tautology. We are
uttering a mere tautology if we mean by '_in_ the mind' the same as by
'_before_ the mind', i.e. if we mean merely being apprehended by the
mind. But if we mean this, we shall have to admit that what, _in this
sense_, is in the mind, may nevertheless be not mental. Thus when we
realize the nature of knowledge, Berkeley's argument is seen to be
wrong in substance as well as in form, and his grounds for supposing
that 'ideas'--i.e. the objects apprehended--must be mental, are found
to have no validity whatever. Hence his grounds in favour of idealism
may be dismissed. It remains to see whether there are any other
grounds.
It is often said, as though it were a self-evident truism, that we
cannot know that anything exists which we do not know. It is inferred
that whatever can in any way be relevant to our experience must be at
least capable of being known by us; whence it follows that if matter
were essentially something with which we could not become acquainted,
matter would be something which we could not know to exist, and which
could have for us no importance whatever. It is generally also
implied, for reasons which remain obscure, that what can have no
importance for us cannot be real, and that therefore matter, if it is
not composed of minds or of mental ideas, is impossible and a mere
chimaera.
To go into this argument fully at our present stage would be
impossible, since it raises points requiring a considerable
preliminary discussion; but certain reasons for rejecting the argument
may be noticed at once. To begin at the end: there is no reason why
what cannot have any _practical_ importance for us should not be real.
It is true that, if _theoretical_ importance is included, everything
real is of _some_ importance to us, since, as persons desirous of
knowing the truth about the universe, we have some interest in
everything that the universe contains. But if this sort of interest
is included, it is not the case that matter has no importance for us,
provided it exists even if we cannot know that it exists. We can,
obviously, suspect that it may exist, and wonder whether it does;
hence it is connected with our desire for knowledge, and has the
importance of either satisfying or thwarting this desire.
Again, it is by no means a truism, and is in fact false, that we
cannot know that anything exists which we do not know. The word
'know' is here used in two different senses. (1) In its first use it
is applicable to the sort of knowledge which is opposed to error, the
sense in which what we know is _true_, the sense which applies to our
beliefs and convictions, i.e. to what are called _judgements_. In
this sense of the word we know _that_ something is the case. This
sort of knowledge may be described as knowledge of _truths_. (2) In
the second use of the word 'know' above, the word applies to our
knowledge of _things_, which we may call _acquaintance_. This is the
sense in which we know sense-data. (The distinction involved is
roughly that between _savoir_ and _connaître_ in French, or between
_wissen_ and _kennen_ in German.)
Thus the statement which seemed like a truism becomes, when re-stated,
the following: 'We can never truly judge that something with which we
are not acquainted exists.' This is by no means a truism, but on the
contrary a palpable falsehood. I have not the honour to be acquainted
with the Emperor of China, but I truly judge that he exists. It may
be said, of course, that I judge this because of other people's
acquaintance with him. This, however, would be an irrelevant retort,
since, if the principle were true, I could not know that any one else
is acquainted with him. But further: there is no reason why I should
not know of the existence of something with which nobody is
acquainted. This point is important, and demands elucidation.
If I am acquainted with a thing which exists, my acquaintance gives me
the knowledge that it exists. But it is not true that, conversely,
whenever I can know that a thing of a certain sort exists, I or some
one else must be acquainted with the thing. What happens, in cases
where I have true judgement without acquaintance, is that the thing is
known to me by _description_, and that, in virtue of some general
principle, the existence of a thing answering to this description can
be inferred from the existence of something with which I am
acquainted. In order to understand this point fully, it will be well
first to deal with the difference between knowledge by acquaintance
and knowledge by description, and then to consider what knowledge of
general principles, if any, has the same kind of certainty as our
knowledge of the existence of our own experiences. These subjects
will be dealt with in the following chapters.
