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

hospes comesque corporis – in the little pineal gland in the midst of the brain, the conception in 
his mind was not unlike that which we have when we picture to ourselves a locomotive engine 
with an engineer in its cab.  The man gives intelligent direction; but, under some circumstances, 
the machine can do a good deal in the absence of the man; if it is started, it can run of itself, and 
to do this, it must go through a series of complicated motions. 
 
Descartes knew that many of the actions performed by the human body are not the result of 
conscious choice, and that some of them are in direct contravention of the will’s commands.  The 
eye protects itself by dropping its lid, when the hand is brought suddenly before it; the foot jerks 
away from the heated object which it has accidentally touched. The body was seen to be a 
mechanism relatively independent of the mind, and one rather complete in itself.  Joined with a 
soul, the circle of its functions was conceived to be widened; but even without the assistance of 
the soul, it was thought that it could keep itself busy, and could do many things that the 
unreflective might be inclined to attribute to the efficiency of the mind. 
 
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 Chap. X – How We Know There Are Other Minds 
 
The bodies of the brutes Descartes regarded as mechanisms of the same general nature as the 
human body.  He was unwilling to allow a soul to any creature below man, so nothing seemed 
left to him save to maintain that the brutes are machines without consciousness, and that their 
apparently purposive actions are to be classed with such human movements as the sudden 
closing of the eye when it is threatened with the hand.  The melancholy results of this doctrine 
made themselves evident among his followers.  Even the mild and pious Malebranche could be 
brutal to a dog which fawned upon him, under the mistaken notion that it did not really hurt a 
dog to kick it. 
 
All this reasoning men have long ago set aside.  For one thing, it has come to be recognized that 
there may be consciousness, perhaps rather dim, blind, and fugitive, but still consciousness, 
which does not get itself recognized as do our clearly conscious purposes and volitions. Many of 
the actions of man which Descartes was inclined to regard as unaccompanied by consciousness 
may not, in fact, be really unconscious. And, in the second place, it has come to be realized that 
we have no right to class all the actions of the brutes with those reflex actions in man which we 
are accustomed to regard as automatic. 
 
The belief in animal automatism has passed away, it is to be hoped, never to return.  That lower 
animals have minds we must believe.  But what sort of minds have they? 
 
It is hard enough to gain an accurate notion of what is going on in a human mind.  Men resemble 
each other more or less closely, but no two are precisely alike, and no two have had exactly the 
same training.  I may misunderstand even the man who lives in the same house with me and is 
nearly related to me.  Does he really suffer and enjoy as acutely as he seems to? or must his 
words and actions be accepted with a discount? The greater the difference between us, the more 
danger that I shall misjudge him.  It is to be expected that men should misunderstand women; 
that men and women should misunderstand children; that those who differ in social station, in 
education, in traditions and habits of life, should be in danger of reading each other as one reads 
a book in a tongue imperfectly mastered.  When these differences are very great, the task is an 
extremely difficult one.  What are the emotions, if he has any, of the Chinaman in the laundry 
near by?  His face seems as difficult of interpretation as are the hieroglyphics that he has pasted 
up on his window. 
 
When we come to the brutes, the case is distinctly worse.  We think that we can attain to some 
notion of the minds to be attributed to such animals as the ape, the dog, the cat, the horse, and it 
is not nonsense to speak of an animal psychology.  But who will undertake to tell us anything 
definite of the mind of a fly, a grasshopper, a snail, or a cuttlefish?  That they have minds, or 
something like minds, we must believe; what their minds are like, a prudent man scarcely even 
attempts to say.  In our distribution of minds may we stop short of even the very lowest animal 
organisms?  It seems arbitrary to do so. 
 
More than that; some thoughtful men have been led by the analogy between plant life and animal 
life to believe that something more or less remotely like the consciousness which we attribute to 
animals must be attributed also to plants.  Upon this belief I shall not dwell, for here we are 
evidently at the limit of our knowledge, and are making the vaguest of guesses.  No one pretends 
 
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 Chap. X – How We Know There Are Other Minds 
that we have even the beginnings of a plant psychology.  At the same time, we must admit that 
organisms of all sorts do bear some analogy to each other, even if it be a remote one; and we 
must admit also that we cannot prove plants to be wholly devoid of a rudimentary consciousness 
of some sort. 
 
As we begin with man and descend the scale of beings, we seem, in the upper part of the series, 
to be in no doubt that minds exist.  Our only question is as to the precise contents of those minds.  
Further down we begin to ask ourselves whether anything like mind is revealed at all. That this 
should be so is to be expected.  Our argument for other minds is the argument from analogy, and 
as we move down the scale our analogy grows more and more remote until it seems to fade out 
altogether.  He who harbors doubts as to whether the plants enjoy some sort of psychic life, may 
well find those doubts intensified when he turns to study the crystal; and when he contemplates 
inorganic matter he should admit that the thread of his argument has become so attenuated that 
he cannot find it at all. 
 
43. THE DOCTRINE OF MIND-STUFF. – Nevertheless, there have been those who have 
attributed something like consciousness even to inorganic matter.  If the doctrine of evolution be 
true, argues Professor Clifford,[4] “we shall have along the line of the human pedigree a series of 
imperceptible steps connecting inorganic matter with ourselves.  To the later members of that 
series we must undoubtedly ascribe consciousness, although it must, of course, have been 
simpler than our own.  But where are we to stop?  In the case of organisms of a certain 
complexity, consciousness is inferred.  As we go back along the line, the complexity of the 
organism and of its nerve-action insensibly diminishes; and for the first part of our course we see 
reason to think that the complexity of consciousness insensibly diminishes also.  But if we make 
a jump, say to the tunicate mollusks, we see no reason there to infer the existence of 
consciousness at all.  Yet not only is it impossible to point out a place where any sudden break 
takes place, but it is contrary to all the natural training of our minds to suppose a breach of 
continuity so great.” 
 
We must not, says Clifford, admit any breach of continuity.  We must assume that consciousness 
is a complex of elementary feelings, “or rather of those remoter elements which cannot even be 
felt, but of which the simplest feeling is built up.”  We must assume that such elementary facts 
go along with the action of every organism, however simple; but we must assume also that it is 
only when the organism has reached a certain complexity of nervous structure that the complex 
of psychic facts reaches the degree of complication that we call Consciousness. 
 
So much for the assumption of something like mind in the mollusk, where Clifford cannot find 
direct evidence of mind.  But the argument does not stop here: “As the line of ascent is unbroken, 
and must end at last in inorganic matter, we have no choice but to admit that every motion of 
matter is simultaneous with some . . . fact or event which might be part of a consciousness.” 
 
Of the universal distribution of the elementary constituents of mind Clifford writes as follows: 
“That element of which, as we have seen, even the simplest feeling is a complex, I shall call