The Project Gutenberg eBook, An Introduction to Philosophy, by George

that man; I want to know what the real external world is.  What shall we say to such a demand? 
 
 
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 Chap. V – Appearances and Realities 
There is a sense in which such a demand is not purely meaningless, though it may not be a very 
sensible demand to make.  We have seen that an increase of knowledge about things compels a 
man to pass from the real things of common life to the real things of science, and to look upon 
the former as appearance.  Now, a man may arbitrarily decide that he will use the word “reality” 
to indicate only that which can never in its turn be regarded as appearance, a reality which must 
remain an ultimate reality; and he may insist upon our telling him about that. How a man not a 
soothsayer can tell when he has come to ultimate reality, it is not easy to see. 
 
Suppose, however, that we could give any one such information.  We should then be telling him 
about things as they are, it is true, but his knowledge of things would not be different in kind 
from what it was before.  The only difference between such a knowledge of things and a 
knowledge of things not known to be ultimate would be that, in the former case, it would be 
recognized that no further extension of knowledge was possible.  The distinction between 
appearance and reality would remain just what it was in the experience of the plain man. 
 
22. THE BUGBEAR OF THE “UNKNOWABLE.” – It is very important to recognize that we 
must not go on talking about appearance and reality, as if our words really meant something, 
when we have quite turned our backs upon our experience of appearances and the realities which 
they represent. 
 
That appearances and realities are connected we know very well, for we perceive them to be 
connected.  What we see, we can touch.  And we not only know that appearances and realities 
are connected, but we know with much detail what appearances are to be taken as signs of what 
realities.  The visual experience which I call the house as seen from a distance I never think of 
taking for a representative of the hat which I hold in my hand.  This visual experience I refer to 
its own appropriate touch thing, and not to another.  If what looks like a beefsteak could really be 
a fork or a mountain or a kitten indifferently, – but I must not even finish the sentence, for the 
words “look like” and “could really be” lose all significance when we loosen the bond between 
appearances and the realities to which they are properly referred. 
 
Each appearance, then, must be referred to some particular real thing and not to any other.  This 
is true of the appearances which we recognize as such in common life, and it is equally true of 
the appearances recognized as such in science.  The pen which I feel between my fingers I may 
regard as appearance and refer to a swarm of moving atoms.  But it would be silly for me to refer 
it to atoms “in general.”  The reality to which I refer the appearance in question is a particular 
group of atoms existing at a particular point in space.  The chemist never supposes that the atoms 
within the walls of his test-tube are identical with those in the vial on the shelf.  Neither in 
common life nor in science would the distinction between appearances and real things be of the 
smallest service were it not possible to distinguish between this appearance and that, and this 
reality and that, and to refer each appearance to its appropriate reality.  Indeed, it is 
inconceivable that, under such circumstances, the distinction should have been drawn at all. 
 
These points ought to be strongly insisted upon, for we find certain philosophic writers falling 
constantly into a very curious abuse of the distinction and making much capital of it.  It is argued 
that what we see, what we touch, what we conceive as a result of scientific observation and 
reflection – all is, in the last analysis, material which is given us in sensation.  The various senses 
 
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 Chap. V – Appearances and Realities 
furnish us with different classes of sensations; we work these up into certain complexes.  But 
sensations are only the impressions which something outside of us makes upon us.  Hence, 
although we seem to ourselves to know the external world as it is, our knowledge can never 
extend beyond the impressions made upon us.  Thus, we are absolutely shut up to appearances, 
and can know nothing about the reality to which they must be referred. 
 
Touching this matter Herbert Spencer writes[1] as follows: “When we are taught that a piece of 
matter, regarded by us as existing externally, cannot be really known, but that we can know only 
certain impressions produced on us, we are yet, by the relativity of thought, compelled to think 
of these in relation to a cause – the notion of a real existence which generated these impressions 
becomes nascent.  If it be proved that every notion of a real existence which we can frame is 
inconsistent with itself, – that matter, however conceived by us, cannot be matter as it actually is, 
– our conception, though transfigured, is not destroyed: there remains the sense of reality, 
dissociated as far as possible from those special forms under which it was before represented in 
thought.” 
 
This means, in plain language, that we must regard everything we know and can know as 
appearance and must refer it to an unknown reality. Sometimes Mr. Spencer calls this reality the 
Unknowable, sometimes he calls it the Absolute, and sometimes he allows it to pass by a variety 
of other names, such as Power, Cause, etc.  He wishes us to think of it as “lying behind 
appearances” or as “underlying appearances.” 
 
Probably it has already been remarked that this Unknowable has brought us around again to that 
amusing “telephone exchange” discussed in the third chapter.  But if the reader feels within 
himself the least weakness for the Unknowable, I beg him to consider carefully, before he pins 
his faith to it, the following: –  
 
(1) If we do perceive external bodies, our own bodies and others, then it is conceivable that we 
may have evidence from observation to the effect that other bodies affecting our bodies may give 
rise to sensations.  In this case we cannot say that we know nothing but sensations; we know real 
bodies as well as sensations, and we may refer the sensations to the real bodies. 
 
(2) If we do not perceive that we have bodies, and that our bodies are acted upon by others, we 
have no evidence that what we call our sensations are due to messages which come from 
“external things” and are conducted along the nerves.  It is then, absurd to talk of such “external 
things” as though they existed, and to call them the reality to which sensations, as appearances, 
must be referred, 
 
(3) In other words, if there is perceived to be a telephone exchange with its wires and 
subscribers, we may refer the messages received to the subscribers, and call this, if we choose, a 
reference of appearance to reality. 
 
But if there is perceived no telephone exchange, and if it is concluded that any wires or 
subscribers of which it means anything to speak must be composed of what we have heretofore 
called “messages,” then it is palpably absurd to refer the “messages” as a whole to subscribers 
not supposed to be composed of “messages”; and it is a blunder to go on calling the things that 
 
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 Chap. V – Appearances and Realities 
we know “messages,” as though we had evidence that they came from, and must be referred to, 
something beyond themselves. 
 
We must recognize that, with the general demolition of the exchange, we lose not only known 
subscribers, but the very notion of a subscriber. It will not do to try to save from this wreck some 
“unknowable” subscriber, and still pin our faith to him. 
 
(4) We have seen that the relation of appearance to reality is that of certain experiences to certain 
other experiences.  When we take the liberty of calling the Unknowable a reality, we blunder in 
our use of the word.  The Unknowable cannot be an experience either actual, possible, or 
conceived as possible, and it cannot possibly hold the relation to any of our experiences that a 
real thing of any kind holds to the appearances that stand as its signs. 
 
(5) Finally, no man has ever made an assumption more perfectly useless and purposeless than the 
assumption of the Unknowable.  We have seen that the distinction between appearance and 
reality is a serviceable one, and it has been pointed out that it would be of no service whatever if 
it were not possible to refer particular appearances to their own appropriate realities.  The 
realities to which we actually refer appearances serve to explain them.  Thus, when I ask: Why 
do I perceive that tree now as faint and blue and now as vivid and green? the answer to the 
question is found in the notion of distance and position in space; it is found, in other words, in a 
reference to the real world of touch things, for which visual experiences serve as signs.  Under 
certain circumstances, the mountain ought to be robed in its azure hue, and, under certain 
circumstances, it ought not. The circumstances in each case are open to investigation. 
 
Now, let us substitute for the real world of touch things, which furnishes the explanation of given 
visual experiences, that philosophic fiction, that pseudo-real nonentity, the Unknowable.  Now I 
perceive a tree as faint and blue, now as bright and green; will a reference to the Unknowable 
explain why the experiences differed?  Was the Unknowable in the one instance farther off in an 
unknowable space, and in the other nearer?  This, even if it means anything, must remain 
unknowable.  And when the chemist puts together a volume of chlorine gas and a volume of 
hydrogen gas to get two volumes of hydrochloric acid gas, shall we explain the change which 
has taken place by a reference to the Unknowable, or shall we turn to the doctrine of atoms and 
their combinations? 
 
The fact is that no man in his senses tries to account for any individual fact by turning for an 
explanation to the Unknowable.  It is a life-preserver by which some set great store, but which no 
man dreams of using when he really falls into the water. 
 
If, then, we have any reason to believe that there is a real external world at all, we have reason to 
believe that we know what it is.  That some know it imperfectly, that others know it better, and 
that we may hope that some day it will be known still more perfectly, is surely no good reason 
for concluding that we do not know it at all. 
 
 [1] “First Principles,” Part I, Chapter IV, section 26. 
 
 
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 Chap. VI – Of Space 
CHAPTER VI 
 
OF SPACE 
 
23. WHAT ARE WE SUPPOSED TO KNOW ABOUT IT. – The plain man may admit that he 
is not ready to hazard a definition of space, but he is certainly not willing to admit that he is 
wholly ignorant of space and of its attributes.  He knows that it is something in which material 
objects have position and in which they move about; he knows that it has not merely length, like 
a line, nor length and breadth, like a surface, but has the three dimensions of length, breadth, and 
depth; he knows that, except in the one circumstance of its position, every part of space is 
exactly like every other part, and that, although objects may move about in space, it is incredible 
that the spaces themselves should be shifted about. 
 
Those who are familiar with the literature of the subject know that it has long been customary to 
make regarding space certain other statements to which the plain man does not usually make 
serious objection when he is introduced to them.  Thus it is said: –  
 
(1) The idea of space is necessary.  We can think of objects in space as annihilated, but we 
cannot conceive space to be annihilated.  We can clear space of things, but we cannot clear away 
space itself, even in thought. 
 
(2) Space must be infinite.  We cannot conceive that we should come to the end of space. 
 
(3) Every space, however small, is infinitely divisible.  That is to say, even the most minute space 
must be composed of spaces.  We cannot, even theoretically, split a solid into mere surfaces, a 
surface into mere lines, or a line into mere points. 
 
Against such statements the plain man is not impelled to rise in rebellion, for he can see that 
there seems to be some ground for making them.  He can conceive of any particular material 
object as annihilated, and of the place which it occupied as standing empty; but he cannot go on 
and conceive of the annihilation of this bit of empty space.  Its annihilation would not leave a 
gap, for a gap means a bit of empty space; nor could it bring the surrounding spaces into 
juxtaposition, for one cannot shift spaces, and, in any case, a shifting that is not a shifting 
through space is an absurdity. 
 
Again, he cannot conceive of any journey that would bring him to the end of space.  There is no 
more reason for stopping at one point than at another; why not go on?  What could end space? 
 
As to the infinite divisibility of space, have we not, in addition to the seeming reasonableness of 
the doctrine, the testimony of all the mathematicians?  Does any one of them ever dream of a line 
so short that it cannot be divided into two shorter lines, or of an angle so small that it cannot be 
bisected? 
 
24. SPACE AS NECESSARY AND SPACE AS INFINITE. – That these statements about space 
contain truth one should not be in haste to deny.  It seems silly to say that space can be 
annihilated, or that one can travel “over the mountains of the moon” in the hope of reaching the 
 
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 Chap. VI – Of Space 
end of it. And certainly no prudent man wishes to quarrel with that coldly rational creature the 
mathematician. 
 
But it is well worth while to examine the statements carefully and to see whether there is not 
some danger that they may be understood in such a way as to lead to error.  Let us begin with the 
doctrine that space is necessary and cannot be “thought away.” 
 
As we have seen above, it is manifestly impossible to annihilate in thought a certain portion of 
space and leave the other portions intact. There are many things in the same case.  We cannot 
annihilate in thought one side of a door and leave the other side; we cannot rob a man of the 
outside of his hat and leave him the inside.  But we can conceive of a whole door as annihilated, 
and of a man as losing a whole hat.  May we or may we not conceive of space as a whole as 
nonexistent? 
 
I do not say, be it observed, can we conceive of something as attacking and annihilating space?  
Whatever space may be, we none of us think of it as a something that may be threatened and 
demolished.  I only say, may we not think of a system of things – not a world such as ours, of 
course, but still a system of things of some sort – in which space relations have no part?  May we 
not conceive such to be possible? 
 
It should be remarked that space relations are by no means the only ones in which we think of 
things as existing.  We attribute to them time relations as well.  Now, when we think of 
occurrences as related to each other in time, we do, in so far as we concentrate our attention upon 
these relations, turn our attention away from space and contemplate another aspect of the system 
of things.  Space is not such a necessity of thought that we must keep thinking of space when we 
have turned our attention to something else.  And is it, indeed, inconceivable that there should be 
a system of things (not extended things in space, of course), characterized by time relations and 
perhaps other relations, but not by space relations? 
 
It goes without saying that we cannot go on thinking of space and at the same time not think of 
space.  Those who keep insisting upon space as a necessity of thought seem to set us such a task 
as this, and to found their conclusion upon our failure to accomplish it.  “We can never represent 
to ourselves the nonexistence of space,” says the German philosopher Kant (1724-1804), 
“although we can easily conceive that there are no objects in space.” 
 
It would, perhaps, be fairer to translate the first half of this sentence as follows: “We can never 
picture to ourselves the nonexistence of space.”  Kant says we cannot make of it a Vorstellung, a 
representation.  This we may freely admit, for what does one try to do when one makes the effort 
to imagine the nonexistence of space?  Does not one first clear space of objects, and then try to 
clear space of space in much the same way?  We try to “think space away,” i.e. to remove it from