ESSAY ON THE HUMAN UNDERSTANDING.
"Were it fit to trouble thee," says Locke in his Epistle to the Reader,
"with the history of this _Essay_, I should tell thee that five or six
friends meeting at my chamber, and discoursing on a subject very remote
from this, found themselves quickly at a stand by the difficulties that
rose on every side. After we had a while puzzled ourselves, without
coming any nearer a resolution of those doubts which perplexed us, it
came into my thoughts that we took a wrong course; and that, before
we set ourselves upon inquiries of that nature, it was necessary to
examine our own abilities, and see what objects our understandings were
or were not fitted to deal with. This I proposed to the company, who
all readily assented; and thereupon it was agreed that this should be
our first inquiry."
This passage may serve not only to describe the occasion of Locke's
_Essay_, but also to indicate the circumstance which constitutes the
peculiar merit and originality of Locke as a philosopher. The science
which we now call Psychology, or the study of mind, had hitherto,
amongst modern writers, been almost exclusively subordinated to the
interests of other branches of speculation. Some exception must,
indeed, be made in favour of Hobbes and Gassendi, Descartes and
Spinoza; but all these authors treated the questions of psychology
somewhat cursorily, while the two former seem usually to have had in
view the illustration of some favourite position in physics or ethics,
the two latter the ultimate establishment of some proposition relating
to the nature or attributes of God. We may say then, without much
exaggeration, that Locke was the first of modern writers to attempt at
once an independent and a complete treatment of the phenomena of the
human mind, of their mutual relations, of their causes and limits. His
object was, as he himself phrases it, "to inquire into the original,
certainty, and extent of human knowledge; together with the grounds
and degrees of belief, opinion, and assent." This task he undertakes
not in the dogmatic spirit of his predecessors, but in the critical
spirit which he may be said to have almost inaugurated. As far as it
is possible for a writer to divest himself of prejudice, and to set to
his work with a candid and open mind, seeking help and information from
all quarters, Locke does so. And the effect of his candour on his first
readers must have been enhanced by the fact, not always favourable to
his precision, that, as far as he can, he throws aside the technical
terminology of the schools, and employs the language current in the
better kinds of ordinary literature and the well-bred society of his
time. The absence of pedantry and of _parti pris_ in a philosophical
work was at that time so rare a recommendation that, no doubt, these
characteristics contributed largely to the rapid circulation and the
general acceptance of the _Essay_.
The central idea, which dominates Locke's work, is that all our
knowledge is derived from experience. But this does not strike us so
much as a thesis to be maintained as a conclusion arrived at after
a vast amount of patient thought and inquiry. Have we any ideas
independent of experience? or, as Locke phrases it, are there any
Innate Principles in the mind?
"It is an established opinion amongst some men that there are in the
Understanding certain Innate Principles, some Primary Notions, κοιναὶ
ἔννοιαι [Greek: koinai ennoiai], characters, as it were, stamped upon
the mind of man, which the Soul receives in its very first being and
brings into the world with it."
This is the opinion which Locke examines and refutes in the first, or
introductory, book of the _Essay_. It has often been objected that he
mistakes and exaggerates the position which he is attacking. And so
far as his distinguished predecessor, Descartes, is concerned (though
to what extent Locke has him in mind, his habit of not referring to
other authors by name prevents us from knowing), this is undoubtedly
the case. For Descartes, though he frequently employs and accepts the
expression "innate notions" or "innate ideas," concedes, as so many
philosophers of the same school have done since, that this native
knowledge is only implicit, and requires definite experiences to
elicit it. Thus, in his notes on the Programme of Regius, he expressly
compares these innate notions or ideas with the nobility which is
characteristic of certain ancient stocks, or with diseases, such as
gout or gravel, which are said to be "innate" in certain families,
not "because the infants of those families suffer from these diseases
in their mother's womb, but because they are born with a certain
disposition or tendency to contract them." Here Descartes seems to
have been on the very point of stumbling on the principle of heredity
which, in the hands of recent physiologists and psychologists, has done
so much towards reconciling rival theories on the nature and origin
of knowledge and clearing up many of the difficulties which attach
to this branch of speculation. It must be confessed, however, that
in his better-known works he often employs unguarded and unexplained
expressions which might easily suggest the crude form of the _à priori_
theory attacked by Locke. Still more is this the case with other
authors, such as Lord Herbert of Cherbury and Dr. Ralph Cudworth, whose
works were in general circulation at the time when Locke was composing
his _Essay_. Lord Herbert, though indeed he acknowledges that "common
notions" (the expression by which he designates _à priori_ principles)
require an object to elicit them into consciousness, seems invariably
to regard them as ready-made ideas implanted in the human mind from
its very origin. They are given by an independent faculty, Natural
Instinct, which is to be distinguished from Internal Sense, External
Sense, and Reasoning ("discursus"), the sources of our other ideas.
They are to be found in every man, and universal consent is the main
criterion by which they are to be discriminated. In fact, there can
be no doubt that the dogma of Innate Ideas and Innate Principles, in
the form attacked by Locke, was a natural, if not the legitimate,
interpretation of much of the philosophical teaching of the time, and
that it was probably the form in which that teaching was popularly
understood. It lay, moreover, as Locke's phrase is, along the "common
road," which was travelled by the majority of men who cared about
speculative subjects at all, and from which it was novel, and therefore
dangerous, to diverge.
The most effective, perhaps, of Locke's arguments against this doctrine
is his challenge to the advocates of Innate Principles to produce
them, and show what and how many they are. Did men find such innate
propositions stamped on their minds, nothing could be more easy than
this. "There could be no more doubt about their number than there is
about the number of our fingers; and 'tis like, then, every system
would be ready to give them us by tale." Now "'tis enough to make
one suspect that the supposition of such innate principles is but an
opinion taken up at random; since those who talk so confidently of
them are so sparing to tell us which they are." (Bk. I., ch. iii., §
14.) The great majority, indeed, of those who maintain the existence
of innate principles and ideas attempt no enumeration of them. Those
who do attempt such an enumeration differ in the lists which they draw
up, and, moreover, as Locke shows in the case of the five practical
principles of Lord Herbert of Cherbury, give no sufficient reason why
many other propositions, which they regard as secondary and derived,
should not be admitted to the same rank with the so-called innate
principles, which they assume to be primary and independent. Locke is
here treading on safer ground than in many of his other criticisms. The
fact is that it is impossible clearly to discriminate between those
propositions which are axiomatic and those which are derived--or, in
the language of the theory which Locke is combating, between those
which are innate and those which are adventitious. Race, temperament,
mental capacity, habit, education, produce such differences between
man and man that a proposition which to one man appears self-evident
and unquestionable will by another be admitted only after considerable
hesitation, while a third will regard it as doubtful, or even false.
Especially is this the case, as Locke does not fail to point out, with
many of the principles of religion and morals, which have now been
received by so constant a tradition in most civilized nations that
they have come to be regarded as independent of reason, and, if not
"ingraven on the mind" from its birth, at least exempt from discussion
and criticism. The circumstance, however, that they are not universally
acknowledged shows that to mankind in general, at any rate, they are
not axiomatic, and that, however clear and convincing the reasons for
them may be, at all events those reasons require to be stated. It was
this determined and vigorous protest against multiplying assumptions
and attempting to withdraw a vast mass of propositions, both
speculative and practical, from the control and revision of reason,
that, perhaps, constituted the most distinctive and valuable part of
Locke's teaching.
* * * * *
Having cleared from his path the theory of Innate Principles, Locke
proceeds, in the Second Book, to inquire how the mind comes to be
furnished with its knowledge. Availing himself of a metaphor which had
been commonly employed by the Stoics, but which reaches as far back
as Aristotle and Plato, and even as Æschylus, he compares the mind to
"white paper, void of all characters, without any ideas," and then asks:
"Whence comes it by that vast store, which the busy and boundless
Fancy of Man has painted on it, with an almost endless variety?
Whence has it all the materials of Reason and Knowledge? To this I
answer in one word, from _Experience_: In that all our knowledge is
founded; and from that it ultimately derives itself. Our observation
employed either about external or sensible objects, or about the
internal operations of our minds perceived and reflected on by our
selves, is that which supplies our Understandings with all the
materials of thinking. These two are the Fountains of Knowledge from
which all the ideas we have, or can naturally have, do spring."
"First, our Senses, conversant about particular sensible objects,
do convey into the mind several distinct perceptions of things,
according to those various ways in which those objects do affect
them. And thus we come by those ideas we have of Yellow, White,
Heat, Cold, Soft, Hard, Bitter, Sweet, and all those which we call
Sensible Qualities, which when I say the senses convey into the mind,
I mean they from external objects convey into the mind what produces
there those Perceptions. This great source of most of the Ideas we
have, depending wholly upon our senses, and derived by them to the
Understanding, I call SENSATION."
"Secondly, the other Fountain, from which Experience furnisheth
the Understanding with Ideas, is the Perception of the operations
of our own minds within us, as it is employed about the ideas it
has got; which operations, when the soul comes to reflect on and
consider, do furnish the Understanding with another set of ideas
which could not be had from things without; and such are Perception,
Thinking, Doubting, Believing, Reasoning, Knowing, Willing, and all
the different actings of our own minds, which we being conscious
of, and observing in our selves, do from these receive into our
Understandings as distinct ideas as we do from bodies affecting
our senses. This source of ideas every man has wholly in himself.
And though it be not sense, as having nothing to do with external
objects, yet it is very like it, and might properly enough be called
Internal Sense. But as I call the other _Sensation_, so I call this
REFLECTION, the ideas it affords being such only as the mind gets by
reflecting on its own operations within itself. By Reflection, then,
in the following part of this Discourse, I would be understood to
mean that notice which the mind takes of its own operations and the
manner of them, by reason whereof there come to be Ideas of these
operations in the Understanding. These two, I say, namely, external
material things, as the objects of Sensation, and the operations of
our own minds within, as the objects of Reflection, are to me the
only originals from whence all our ideas take their beginning. The
term operations here I use in a large sense, as comprehending not
barely the actions of the mind about its ideas, but some sort of
passions arising sometimes from them, such as is the satisfaction or
uneasiness arising from any thought."
"The Understanding seems to me not to have the least glimmering of
any ideas which it doth not receive from one of these two. External
objects furnish the mind with the ideas of sensible qualities, which
are all those different perceptions they produce in us; and the mind
furnishes the Understanding with ideas of its own operations." (Bk.
II., ch. i., §§ 2-5.)
In deriving our knowledge from two distinct sources, Sensation and
Reflection, Locke is advancing a position altogether different
from that of what is properly called the Sensationalist school of
philosophers. Gassendi and Hobbes before him, Condillac and Helvétius
after him, found the ultimate source of all our knowledge in the
impressions of sense. The emphatic words of Hobbes, standing in the
forefront of the _Leviathan_, are:--"The original of all the thoughts
of men is that which we call Sense, for there is no conception in a
man's mind which hath not at first, totally or by parts, been begotten
upon the organs of sense." And Condillac, aiming at a theory still more
simple, derives from sensations not only all our knowledge but all our
faculties. "The other fountain," then, of Locke has, we must recollect,
a peculiar significance as distinguishing his psychology from that
of the sensationalist writers who preceded and who followed him. His
theory of the origin of knowledge may fairly be called an experiential,
but it cannot with any truth be called a sensationalist theory.
The rest of the Second Book of the _Essay_ is mainly taken up with the
attempt to enumerate our simple ideas of Sensation and Reflection, and
to resolve into them our other ideas, however complex. To follow Locke
into these details would be to re-write the _Essay_. I propose simply
to direct the attention of the reader to a few salient points.
Of "Simple Ideas of Sensation," some "come into our minds by one Sense
only." Such are the various colours, sounds, tastes, and smells, Heat
and Cold, and the sensation of Resistance or Impenetrability, which
Locke denominates Solidity. "The Ideas we get by more than one sense
are of Space or Extension, Figure, Rest, and Motion."
The "Simple Ideas of Reflection," which the mind acquires, when "it
turns its view inward upon itself, and observes its own actions about
those ideas it has received from without," are mainly two, namely,
Perception or Thinking, and Volition or Willing.
"There be other simple ideas, which convey themselves into the mind by
all the ways of Sensation and Reflection, namely, Pleasure or Delight,
Pain or Uneasiness, Power, Existence, Unity. (Bk. II., ch. vii., § 1.)
"These simple ideas, the materials of all our knowledge, are
suggested and furnished to the mind only by those two ways above
mentioned, namely, Sensation and Reflection. When the Understanding
is once stored with these simple ideas, it has the power to repeat,
compare, and unite them, even to an almost infinite variety, and so
can make at pleasure new complex ideas. But it is not in the power of
the most exalted Wit or enlarged Understanding, by any quickness or
variety of thoughts, to invent or frame one new simple idea in the
mind, not taken in by the ways before mentioned. Nor can any force
of the Understanding destroy those that are there: the dominion of
man, in this little world of his own understanding, being much-what
the same as it is in the great world of visible things, wherein his
power, however managed by art and skill, reaches no farther than to
compound and divide the materials that are made to his hand, but can
do nothing towards the making the least particle of new matter or
destroying one atom of what is already in being. The same inability
will every one find in himself who shall go about to fashion in his
Understanding any simple idea not received in by his senses from
external objects or by reflection from the operations of his own mind
about them." (Bk. II., ch. ii., § 2.)
In the reception of these simple ideas, Locke regards the mind as
merely passive. It can no more refuse to have them, alter or blot
them out, than a mirror can refuse to receive, alter, or obliterate
the images reflected on it. The Understanding, before the entrance of
simple ideas, is like a dark room, and external and internal sensation
are the windows by which light is let in. But when the light has once
penetrated into this dark recess, the Understanding has an almost
unlimited power of modifying and transforming it. It can create complex
ideas, and that in an infinite variety, out of its simple ideas, and
this it does chiefly by combining, comparing, and separating them.
"This shows man's power, and its way of operation, to be much what
the same in the material and intellectual world. For the materials in
both being such as he has no power over, either to make or destroy,
all that man can do is either to unite them together, or to set them
by one another, or wholly separate them." (Bk. II., ch. xii., § 1.)
The complex ideas are classified under three heads, modes, which may
be either simple or mixed, substances, and relations. Here, however,
my analysis must stop, and I must content myself with giving a few
examples of the manner in which Locke attempts to resolve "complex
ideas" into "simple" ones.
The idea of Infinity, to take one of his most celebrated resolutions,
is merely a simple mode of Quantity, as Immensity is a simple mode of
Space, and Eternity of Duration. All alike are negative ideas, arising
whenever we allow the mind "an endless progression of thought," without
any effort to arrest it. "How often soever" a man doubles an unit
of space, be it a "mile, or diameter of the earth, or of the _Orbis
Magnus_," or any otherwise multiplies it, "he finds that, after he has
continued this doubling in his thoughts and enlarged his idea as much
as he pleases, he has no more reason to stop, nor is one jot nearer the
end of such addition, than he was at first setting out; the power of
enlarging his idea of Space by farther additions remaining still the
same, he hence takes idea of infinite space." (Bk. II., ch. xvii., § 3.)
With the idea of "Substance" Locke is fairly baffled. If we examine our
idea of a horse, a man, a piece of gold, &c., we are able to resolve
it into a number of simple ideas, such as extension, figure, solidity,
weight, colour, &., co-existing together. But, according to Locke, who,
in this respect, was merely following in the track of the generally
received philosophy of his time, there is, in addition to all these
qualities, a _substratum_ in which they inhere, or, to use his own
language, "wherein they do subsist, and from which they do result."
Now of the various qualities we can form a clear idea and give a more
or less intelligible account. But can we form a clear idea or give an
intelligible account of the substratum? Locke here is bold enough to
break off from the orthodox doctrine of the time, and confess candidly
that we cannot. The idea of this Substratum or Substance is a "confused
idea of something to which the qualities belong, and in which they
subsist." The name Substance denotes a Support, "though it be certain
we have no clear or distinct idea of that thing we suppose a support."
"So that if any one will examine himself concerning his notion of
pure Substance in general, he will find he has no other idea of it
at all but only a supposition of he knows not what Support of such
qualities which are capable of producing simple ideas in us; which
qualities are commonly called Accidents. If any one should be asked
what is the subject wherein Colour or Weight inheres, he would have
nothing to say but the solid extended parts. And if he were demanded
what is it that Solidity and Extension inhere in, he would not be in
a much better case than the Indian who, saying that the world was
supported by a great elephant, was asked what the elephant rested on?
To which his answer was, a great tortoise. But, being again pressed
to know what gave support to the broad-backed tortoise, replied,
something, he knew not what. And thus here, as in all other cases,
where we use words without having clear and distinct ideas, we talk
like children; who, being questioned what such a thing is, which
they know not, readily give this satisfactory answer, That it is
something; which in truth signifies no more, when so used, either by
children or men, but that they know not what, and that the thing they
pretend to know and talk of is what they have no distinct idea of at
all, and so are perfectly ignorant of it and in the dark." (Bk. II.,
ch. xxiii., § 2.)
No wonder that the next step in philosophy was to get rid altogether of
this "something, we know not what." For, if we know not what it is, how
do we know that it exists, and is not a mere fiction of the Schools?
This step was taken by Berkeley, as respects matter, and by Hume the
same negative criticism which Berkeley confines to matter was boldly,
and, as it seems to me, far less successfully and legitimately extended
to mind. Indeed, were it not for his express assurance to the contrary,
we should often be tempted to think that Locke himself regarded this
distinction of Substance and Accident, so far, at least, as it affects
Matter and its attributes, as untenable, and was anxious to insinuate a
doubt as to the very existence of the "unknown somewhat."
In this chapter, Locke maintains that there is no more difficulty, if
indeed so much, in the notion of immaterial spirit as of body. "Our
idea of Body, as I think, is an extended solid substance, capable
of communicating motion by impulse; and our idea of our Soul, as an
immaterial Spirit, is of a substance that thinks, and has a power
of exciting motion in body by Will or Thought." (§ 22.) Now, it is
"no more a contradiction that Thinking should exist separate and
independent from Solidity, than it is a contradiction that Solidity
should exist separate and independent from Thinking, they being both
but simple ideas independent one from another. And, having as clear
and distinct ideas in us of Thinking as of Solidity, I know not why
we may not as well allow a thinking thing without solidity, that is
immaterial, to exist, as a solid thing without thinking, that is
matter, to exist; especially since it is no harder to conceive how
Thinking should exist without Matter, than how Matter should think." (§
32.)
In the Fourth Book (ch. iii., § 6), however, he gave great scandal by
suggesting the possibility that Matter might think, that it was not
much more repugnant to our conceptions that God might, if he pleased,
"superadd to Matter a Faculty of Thinking, than that he should superadd
to it another substance with a faculty of thinking." At the same time,
he regarded it as no less than a contradiction to suppose that Matter,
"which is evidently in its own nature void of sense and thought,"
should be the "eternal first thinking Being," or God Himself; and, in
his First Letter to the Bishop of Worcester, he grants that _in us_
(as distinguished from the lower animals) it is in the highest degree
probable that the "thinking substance" is immaterial. Materialism,
therefore, as ordinarily understood, is certainly no part of Locke's
system.
In discussing the idea of Substance, Locke seems generally to be
thinking more of Matter than Mind. But, in an early part of the _Essay_
(Bk. II., ch. xiii., § 18), he very rightly begs those who talk so much
of Substance "to consider whether applying it, as they do, to the
infinite incomprehensible God, to finite Spirit, and to Body, it be
in the same sense, and whether it stands for the same idea, when each
of those three so different beings are called Substances." As applied
respectively to Matter and to Mind (whether finite or infinite), it
appears to me that the word Substance assumes a very different meaning,
and that the absurdities which it is possible to fix on the distinction
between Matter and its attributes by no means extend to the distinction
between Mind and its operations. For an union of certain forces or
powers affecting our organisms in certain ways seems to exhaust our
conception of external objects (the notion of externality, I conceive,
being quite independent of that of the Substrate "matter"), but no
similar enumeration of mental acts and feelings seems adequately to
take the place of that "Self," or "I," of which we regard these as
merely phases and modifications. It would much conduce to clearness
in philosophical discussions if, at least amongst those who admit the
dualism of matter and mind, the word Substance, whenever applied to
incorporeal objects, were replaced by the word Mind, and, whenever
applied to corporeal objects, by the word Matter.
* * * * *
The Second Book closes, in the Fourth and subsequent editions, with a
short but very interesting Chapter on the "Association of Ideas." The
student of Mental Philosophy will find it instructive to compare this
Chapter with the previous account given by Hobbes (_Human Nature_, ch.
iv.; _Leviathan_, Pt. I., ch. iii.), and the subsequent account given
by Hume (_Human Nature_, Pt. I., § 4; _Essays on Human Understanding_,
§ 3), of the same phenomena. Locke appears to have been the first
author to use the exact[2] expression "Association of Ideas," and it
is curious to find in this chapter (§ 5) the word "inseparable," so
familiar to the readers of recent works on psychology, already applied
to designate certain kinds of association. Some ideas, indeed, have,
he says, a natural correspondence, but others, that "in themselves are
not at all of kin," "come to be so united in some men's minds that one
no sooner at any time comes into the understanding than the whole Gang,
always inseparable, show themselves together."
[2] Sir W. Hamilton refers to La Chambre (_Système de l'Ame_:
Paris, 1664) as having anticipated Locke in the use of this
expression. In Liv. IV., ch. ii., art. 9, La Chambre speaks
of "l' Union et la Liaison des Images," but I cannot find
that he approaches any nearer to the now established
phraseology.
The following passage on what may be called the associations of
antipathy affords a good instance of Locke's power of homely and
apposite illustration:
"Many children imputing the pain they endured at school to their
books they were corrected for, so join those ideas together, that a
book becomes their aversion, and they are never reconciled to the
study and use of them all their lives after; and thus reading becomes
a torment to them, which otherwise possibly they might have made the
great pleasure of their lives. There are rooms convenient enough,
that some men cannot study in, and fashions of vessels, which though
never so clean and commodious, they cannot drink out of, and that by
reason of some accidental ideas which are annexed to them and make
them offensive. And who is there that hath not observed some man to
flag at the appearance or in the company of some certain person not
otherwise superior to him, but because, having once on some occasion
got the ascendant, the idea of authority and distance goes along with
that of the person, and he that has been thus subjected is not able
to separate them."
Had Locke's _Essay_ ended with the Second Book, we should hardly
have detected in it any incompleteness. It might have been regarded
as an analytical work on the nature and origin of our ideas, or, in
other words, on the elements of our knowledge. There are, however,
a third and fourth book--the former treating "Of Words," the latter
"Of Knowledge and Opinion." Locke's notion appears to have been that,
after treating of "Ideas," mainly as regarded in themselves, it was
desirable to consider them as combined in Judgments or Propositions,
and to estimate the various degrees of assent which we give or ought to
give to such judgments, when formed. The Fourth Book thus, to a certain
extent, takes the place, and was probably designed to take the place,
of the Logic of the Schools. "But," to quote Locke's own language in
the Abstract of the _Essay_, "when I came a little nearer to consider
the nature and manner of human knowledge, I found it had so much to do
with propositions, and that words, either by custom or necessity, were
so mixed with it, that it was impossible to discourse of knowledge with
that clearness we should, without saying something first of words and
language."
The last three Chapters of the Third Book are remarkable for their
sound sense, and may still be read with the greatest advantage by
all who wish to be put on their guard against the delusions produced
by misleading or inadequate language--those "Idola Fori" which Bacon
describes as the most troublesome of the phantoms which beset the mind
in its search for truth. Some of the best and freshest of Locke's
thoughts, indeed, are to be found in this book, and especially in the
less technical parts of it.
The Fourth Book, under the head of Knowledge, treats of a great
variety of interesting topics: of the nature of knowledge, its
degrees, its extent, and reality; of the truth and certainty of
Universal Propositions; of the logical axioms, or laws of thought;
of the evidence for the existence of a God; of Faith and Reason; of
the Degrees of Assent; of Enthusiasm; of Error. Into these attractive
regions it is impossible that I can follow my author, but the reader
who wishes to see examples of Locke's strong practical sense and, at
the same time, to understand the popularity so soon and so constantly
accorded to the _Essay_, should make acquaintance at least with the
four chapters last named.
* * * * *
From the task of description I now pass to that of criticism, though
this must be confined within still narrower limits than the former, and
indeed, amongst the multiplicity of subjects which invite attention, I
must confine myself to one only: the account of the ultimate origin of
our knowledge, which forms the main subject of the _Essay_.
Locke, as we have seen, derived all our knowledge from Experience. But
experience, with him, was simply the experience of the individual.
In order to acquire this experience, it was indeed necessary that we
should have certain "inherent faculties." But of these "faculties" he
gives no other account than that God has "furnished" or "endued" us
with them. Thus, the _Deus ex machina_ was as much an acknowledged
necessity in the philosophy of Locke, and was, in fact, almost as
frequently invoked, as in that of his antagonists. Is there any
natural account to be given of the way in which we come to have these
"faculties," of the extraordinary facility we possess of acquiring
simple and forming complex ideas, is a question which he appears never
to have put to himself. Inquiries of this kind, however, we must
recollect, were foreign to the men of his generation, and, in fact,
have only recently become a recognized branch of mental philosophy.
Hence it was that his system left so much unexplained. Not only the
very circumstance that we have "inherent faculties" at all, but the
wide differences of natural capacity which we observe between one man
or race and another, and the very early period at which there spring up
in the mind such notions as those of space, time, equality, causality,
and the like, are amongst the many difficulties which Locke's theory,
in its bare and unqualified form, fails satisfactorily to answer. It
was thus comparatively easy for Kant to show that the problem of the
origin of knowledge could not be left where Locke had left it; that
our _à posteriori_ experiences presuppose and are only intelligible
through certain _à priori_ perceptions and conceptions which the mind
itself imposes upon them; or, to use more accurate language, through
certain _à priori_ elements in our perceptions and conceptions, which
the mind contributes from itself. Thus the child appears, as soon
as it is capable of recognizing any source of its impressions, to
regard an object as situated in space, an event as happening in time,
circumstances which have occurred together as likely to occur together
again. But Kant's own account was defective in leaving this _à priori_
element of our knowledge unexplained, or, at least, in attempting no
explanation of it. The mind, according to him, is possessed of certain
Forms and Categories, which shape and co-ordinate the impressions
received from the external world, being as necessary to the acquisition
of experience, as experience is necessary to eliciting them into
consciousness. But here his analysis ends. He does not ask how the
mind comes to be possessed of these Forms and Categories, nor does he
satisfactorily determine the precise relation in which they stand to
the empirical elements of knowledge. When studying his philosophy,
we seem indeed to be once more receding to the mysterious region of
Innate Ideas. But the mystery is removed at least several stages back,
if we apply to the solution of these mental problems the principle
of Heredity, which has recently been found so potent in clearing up
many of the difficulties connected with external nature. What are the
"Innate Ideas" of the older philosophers, or the Forms and Categories
of Kant, but certain _tendencies_ of the mind to group phenomena, the
"fleeting objects of sense," under certain relations and regard them
under certain aspects? And why should these tendencies be accounted
for in any other way than that by which we are accustomed to account
for the tendency of an animal or plant, belonging to any particular
species, to exhibit, as it developes, the physical characteristics of
the species to which it belongs? The existence of the various mental
tendencies and aptitudes, so far as the individual is concerned, is,
in fact, to be explained by the principle of hereditary transmission.
But how have these tendencies and aptitudes come to be formed in the
race? The most scientific answer is that which, following the analogy
of the theory now so widely admitted with respect to the physical
structure of animals and plants, assigns their formation to the
continuous operation, through a long series of ages, of causes acting
uniformly, or almost uniformly, in the same direction--in one word, of
Evolution. This explanation may have its difficulties, but it is at any
rate an attempt at a natural explanation where no other such attempt
exists, and it has the merit of falling in with the explanations of
corresponding phenomena now most generally accepted amongst scientific
men in other departments of knowledge.
According to this theory, there is both an _à priori_ and an _à
posteriori_ element in our knowledge, or, to speak more accurately,
there are both _à priori_ and _à posteriori_ conditions of our knowing,
the _à posteriori_ condition being, as in all systems, individual
experience, the _à priori_ condition being inherited mental aptitudes,
which, as a rule, become more and more marked and persistent with
each successive transmission. Now Locke lays stress simply upon the
_à posteriori_ condition, though he recognizes a certain kind of _à
priori_ condition in our "natural faculties," and the simple ideas
furnished by reflecting on their operations. The very important
condition, however, of inherited aptitudes facilitating the formation
of certain general conceptions concurrently, or almost concurrently,
with the presentation of individual experiences, did not occur to him
as an element in the solution of the problem he had undertaken to
answer, nor, in that stage of speculation, could it well have done
so. His peculiar contribution to the task of solving this question
consisted in his skilful and popular delineation of the _à posteriori_
element in knowledge, and in his masterly exposure of the insufficiency
of the account of the _à priori_ element, as then commonly given.
Locke's own theory was afterwards strained by Hume and Hartley, and
still more by his professed followers in France, such as Condillac
and Helvétius, till at last, in the opinion of most competent judges,
it snapped asunder. Then, under the massive, though often partial and
obscure, treatment of Kant, came the rehabilitation of the _à priori_
side of knowledge. In recent times, mainly by aid of the light thrown
on it from other branches of inquiry, a more thorough and scientific
treatment of psychology has done much, as I conceive, towards
completing and reconciling the two divergent theories which at one
time seemed hopelessly to divide the world of philosophic thinkers.
And yet, as it appears to me, the ultimate mystery which surrounds
the beginnings of intellectual life on the globe has by no means been
removed.
As closely connected with this general criticism of Locke's system, or
rather as presenting the defects just criticised under another form, I
may notice the tendency of the _Essay_ to bring into undue prominence
the passive receptivities of the Mind, and to ignore its activity and
spontaneity. The metaphor of the _tabula rasa_, the sheet of "white
paper," once admitted, exercises a warping influence over the whole
work. The author is so busied with the variety of impressions from
without, that he seems sometimes almost to ignore the reaction of the
mind from within. And yet this one-sideness of Locke's conception
of mind may easily be exaggerated. "When the Understanding is once
stored with simple ideas, it has the power to repeat, compare, and
unite them, even to an almost infinite variety, and so can make at
pleasure new complex ideas." (Bk. II., ch. ii., § 2.) Moreover, amongst
the simple ideas themselves are the ideas of Reflection, "being such
as the mind gets by reflecting on its own operations." The system,
in fact, assumes an almost ceaseless activity of mind, after the
simple ideas of sensation have once entered it. But where it fails
is in not recognizing that mental reaction which is essential to the
formation of even the simple ideas of sensation themselves, as well
as that spontaneous activity of mind which often seems to assert
itself independently of the application of any stimulus from without.
Here again a more scientific psychology than was possible in Locke's
day comes to our aid, and shows, as is done by Mr. Bain and other
recent writers, that the nerves, stored with energy, often discharge
themselves of their own accord, and that movement is at least as much
an original factor in animal life as is sensation, while sometimes
it even precedes it in time. Had the constant interaction of mental
activity and mental receptivity, producing a compound in which it
is often almost impossible to disentangle the elements, been duly
recognized by Locke, it would certainly have made his philosophy less
simple, but it would have made it more true to facts. Physiology,
however, was in his days in far too backward a state itself to throw
much light upon Psychology. And the reaction against the prevailing
doctrine of Innate Ideas naturally led to a system in which the
influences of external circumstances, of education and habit, were
exaggerated at the expense of the native powers, or as they might more
appropriately be called the inherited aptitudes, and the spontaneous
activity of the mind.
Here, tempting as it is to follow my author along the many tracks of
psychological, metaphysical, and logical discussion which he always
pursues with sagacity, candour, and good sense, if not always with the
consistency and profundity which we should require from later writers,
my criticism must necessarily end.
Before, however, finally dismissing the _Essay_, I must pause to ask
what was the main work in the history of philosophy and thought which
it accomplished. Many of its individual doctrines, doubtless, could not
now be defended against the attacks of hostile criticism, and some even
of those which are true in the main, are inadequate or one-sided. But
its excellence lies in its tone, its language, its method, its general
drift, its multiplicity of topics, the direction which it gave to the
thoughts and studies of reflecting men for many generations subsequent
to its appearance. Of the tone of candour and open-mindedness which
pervades it, of the unscholastic and agreeable form in which it is
written, and of the great variety of interesting topics which it
starts, I have spoken already. Its method, though not absolutely new,
even in modern times, for it is at least, to some extent, the method
of Descartes, if not, in a smaller degree, of Hobbes and Gassendi, was
still not common at the time of its appearance. Instead of stating
a series of preconceived opinions, or of dogmas borrowed from some
dominant school, in a systematic form, Locke sets to work to examine
the structure of his own mind, and to analyze into their elements the
ideas which he finds there. This, the _introspective_ method, as it
has been called, though undoubtedly imperfect, for it requires to be
supplemented by the study of the minds of other men, if not of the
lower animals, as made known by their acts, and words, and history,
is yet a great advance on the purely _à priori_, and often fanciful,
methods which preceded it. Nor do we fail to find in the _Essay_ some
employment of that _comparative_ method to which I have just alluded:
witness the constant references to children and savages in the first
book, and the stress which is laid on the variety of moral sentiment
existing amongst mankind. This inductive treatment of philosophical
problems, mainly introspective, but in some measure also comparative,
which was extremely rare in Locke's time, became almost universal
afterwards. Closely connected with the method of the book is its
general purport. By turning the mind inwards upon itself, and "making
it its own object," Locke surmises that all its ideas come either
from without or from experience of its own operations. He finds, on
examination and analysis, no ideas which cannot be referred to one or
other of these two sources. The single word "experience" includes
them both, and furnishes us with a good expression for marking the
general drift of his philosophy. It was pre-eminently a philosophy of
experience, both in its method and in its results. It accepts nothing
on authority, no foregone conclusions, no data from other sciences.
It digs, as it were, into the mind, detaches the ore, analyzes it,
and asks how the various constituents came there. The analytical and
psychological direction thus given to philosophy by Locke was followed
by most of the philosophical writers of the eighteenth century. However
divergent in other respects, Hume and Berkeley, Hartley and Reid, the
French Sensationalists, Kant, all commence their investigations by
inquiring into the constitution, the capacities, and the limits of
the Human Mind. Nor can any system of speculation be constructed on a
sound basis which has neglected to dig about the foundations of human
knowledge, to ascertain what our thoughts can and what they cannot
compass, and what are the varying degrees of assurance with which the
various classes of propositions may be accepted by us. Two cautions,
indeed, are necessary in applying this procedure. We must never forget
that the mind is constantly in contact with external nature, and that
therefore a constant action and reaction is taking place between them;
and we must never omit to base our inductions on an examination of
other minds as well as our own, bringing into the account, as far as
possible, every type and grade of mental development.
It was not, however, only its general spirit and direction which Locke
impressed on the philosophy of the eighteenth century. He may almost
be said to have recreated that philosophy. There is hardly a single
French or English writer (and we may add Kant) down to the time of
Dugald Stewart, or even of Cousin, Hamilton, and J. S. Mill, who
does not profess either to develope Locke's system, or to supplement,
or to criticise it. Followers, antagonists, and critics alike seem
to assume on the part of the reader a knowledge of the _Essay on the
Human Understanding_, and to make that the starting-point of their own
speculations. The office which Bacon assigns to himself with reference
to knowledge generally might well have been claimed by Locke with
reference to the science of mind. Both of them did far more than merely
play the part of a herald, but of both alike it was emphatically true
that they "rang the bell to call the other wits together."