118. A genius of such native force as Locke’s could not be applied

to philosophy without determining the lines of future speculation,

even though to itself they remained obscure. He stumbles upon truths

when he is not looking for them, and the inconsistencies or accidents

of his system are its most valuable part. Thus, in a certain sense,

he may claim the authorship at once of the popular empiricism of

the modern world, and of its refutation. He fixed the prime article

of its creed, that thought has nothing to do with the constitution

of facts, but only with the representation of them by signs and the

rehearsal to itself of what its signs have signified--in brief, that

its function is merely the analytical judgment; yet his admissions

about mathematical knowledge rendered inevitable the Kantian

question, ‘How are synthetic judgments á-priori possible?’--which was

to lead to the recognition of thought as constituting the objective

world, and thus to get rid of the antithesis between thought and

reality. In his separation of the datum of experience from the work

of thought he was merely following the Syllogistic Logic, which

really assigns no work to the thought, whose office it professes to

magnify, but the analysis of given ideas. Taking the work as that

Logic conceived it (and as it must be conceived if the separation is

to be maintained) he showed--conclusively as against Scholasticism--

the ‘trifling’ character of the necessary and universal truths with

which it dealt. Experience, the manifestation of the real, regarded

as a series of events which to us are sensations, can only yield

propositions singular as the events, and having a truth like them

contingent. By consequence, necessity and universality of connection

can only be found in what the mind does for itself, without reference

to reality, when it analyses the complex idea which it retains as

the memorandum of its past single experiences; _i.e._, in a relation

between ideas or propositions of which one explicitly includes the

other. Upon this relation syllogistic reasoning rests, and, except

so far as it may be of use for convicting an opponent (or oneself)

of inconsistency, it has nothing to say against such nominalism

as the above. Hence, with those followers of Locke who have been

most faithful to their master, it has remained the standing rule

to make the generality of a truth consist in its being analytical

of the meaning of a name, and its necessity in its being included

in one previously conceded. Yet if such were the true account of

the generality and necessity of mathematical propositions, their

truth according to Locke’s explicit statement would be ‘verbal and

trifling,’ not, as it is, ‘real and instructive.’

Fatal to the notion that mathematical truths, though general, are got

from experience:

119. The point of this, the most obvious, contradiction inherent

in Locke’s empiricism, is more or less striking according to the

fidelity with which the notion of matter-of-fact, or of the reality

that is not of the mind, proper to that system, is adhered to.

When the popular Logic derived from Locke has so far forgotten

the pit whence it was digged as to hold that propositions of a

certainty at once real and general can be derived from experience,

and to speak without question of ‘general matters-of-fact’ in a

sense which to Locke almost, to Hume altogether, would have been

a contradiction in terms, it naturally finds no disturbance in

regarding mathematical certainty as different not in kind, but only

in degree, from that of any other ‘generalisation from experience.’

Not aware that the distinction of mathematical from empirical

generality is the condition upon which, according to Locke, the

former escapes condemnation as ‘trifling,’ it does not see any need

for distinguishing the sources from which the two are derived, and

hence goes on asserting against imaginary or insignificant opponents

that mathematical truth is derived from ‘experience;’ which, if

‘experience’ be so changed from what Locke understood by it as to

yield general propositions concerning matters-of-fact of other than

analytical purport, no one need care to deny. That it can yield such

propositions is, doubtless, the supposition of the physical sciences;

nor, we must repeat, is it the _correctness_ of this supposition

that is in question, but the validity, upon its admission, of that

antithesis between experience and the work of thought, which is the

‘be-all and end-all’ of the popular Logic.

... and to received views of natural science: but Locke not so clear

about this.

120. Locke, as we have seen, after all the encroachments made

unawares by thought within the limits of that experience which he

opposes to it--or, to put it conversely, after all that he allows

‘nature’ to take without acknowledgment from ‘mind’--is still so far

faithful to the opposition as to ‘suspect a science of nature to be

impossible.’ This suspicion, which is but a hesitating expression

of the doctrine that general propositions concerning substances are

merely verbal, is the exact counterpart of the doctrine pronounced

without hesitation that mathematical truths, being at once real and

general, do not concern nature at all. Real knowledge concerning

nature being given by single impressions of bodies at single times

operating upon us, and by consequence being expressible only in

singular propositions, any reality which general propositions state

must belong merely to the mind, and a mind which can originate a

reality other than nature’s cannot be a passive receptacle of natural

impressions. Locke admits the real generality of mathematical truths,

but does not face its consequences. Hume, seeing the difficulty, will

not admit the real generality. The modern Logic, founded on Locke,

believing in the possibility of propositions at once real and general

concerning nature. does not see the difficulty at all. It reckons

mathematical to be the same in kind with natural knowledge, each

alike being real notwithstanding its generality; not aware that by

so doing, instead of getting rid, as it fancies, of the originative

function of thought in respect of mathematical knowledge, it only

necessitates the supposition of its being originative in respect of

the knowledge of nature as well.

Ambiguity as to real essence causes like ambiguity as to science of

nature. Particular experiment cannot afford general knowledge.

121. It may find some excuse for itself in the hesitation with

which Locke pronounces the impossibility of real generality in

the knowledge of nature--an hesitation which necessarily results

from the ambiguities, already noticed, in his doctrine of real and

nominal essence. So far as the opposition between the nominal and

real essences of substances is maintained in its absoluteness, as

that between every possible collection of ideas on the one side, and

something wholly apart from thought on the other, this impossibility

follows of necessity. But so far as the notion is admitted of

the nominal essence being in some way, however inadequately,

representative of the real, there is an opening, however indefinite,

for general propositions concerning the latter. On the one hand we

have the express statement that ‘universal propositions, of whose

truth and falsehood we can have certain knowledge, concern not

existence’ (Book IV. chap. ix. sec. 1). They are founded only on the

‘relations and habitudes of abstract ideas’ (Book IV. chap xii. sec.

7); and since it is the proper operation of the mind in abstraction

to consider an idea under no other existence but what it has in the

understanding, they represent no knowledge of _real_ existence at all

(Book IV. chap. ix. sec. 1). Here Locke is consistently following

his doctrine that the ‘particularity in time,’ of which abstraction

is made when we consider ideas as in the understanding, is what

specially distinguishes the real; which thus can only be represented

by ‘actually present sensation.’ It properly results from this

doctrine that the proposition representing particular experiment and

observation is only true of real existence so long as the sensation,

in which the experiment consists, continues present. Not only is the

possibility excluded of such experiment yielding a certainty which

shall be general as well as real, but the particular proposition

itself can only be _really_ true so far as the qualities, whose

co-existence it asserts, are present sensations. The former of these

limitations to real truth we find Locke generally recognising, and

consequently suspecting a science of nature to be impossible; but

the latter, which would be fatal to the supposition of there being a

real nature at all, even when he carries furthest the reduction of

reality to present feeling, he virtually ignores. On the other hand,

there keeps appearing the notion that, inasmuch as the combination

of ideas which make up the nominal essence of a substance is taken

from a combination in nature or reality, whenever the connexion

between any of these is necessary, it warrants a proposition

_universally_ true in virtue of the necessary connexion between the

ideas, and _really_ true in virtue of the ideas being taken from

reality. According to this notion, though ‘the certainty of universal

propositions concerning substances is very narrow and scanty,’ it is

yet possible (Book IV. chap. vi. sec. 13). It is not recognised as

involving that contradiction which it must involve if the antithesis

between reality and ideas in the mind is absolutely adhered to. Nay,

inasmuch as certain ideas of primary qualities, _e.g._ those of

solidity and of the receiving or communicating motion upon impulse,

are necessarily connected, it is supposed actually to exist (Book

IV. chap iii. sec. 14). It is only because, as a matter of fact, our

knowledge of the relation between secondary qualities and primary is

so limited that it cannot be carried further. That they are related

as effects and causes, it would seem, we know; and that the ‘causes

work steadily, and effects constantly flow from them,’ we know also;

but ‘their connexions and dependencies are not discoverable in our

ideas’ (Book IV. chap. iii. sec. 29). That, if discoverable in our

ideas, just because there discovered, the connexion would not be a

real co-existence, Locke never expressly says. He does not so clearly

articulate the antithesis between relations of ideas and matters

of fact. If he had done so, he must also have excluded from real

existence those abstract ideas of body which constitute the scanty

knowledge of it that according to him we do possess (Book IV. chap.

iii. sec. 24). He is more disposed to sigh for discoveries that would

make physics capable of the same general certainty as mathematics,

than to purge the former of those mathematical propositions--really

true only because having no reference to reality--which to him formed

the only scientific element in them.

What knowledge it can afford, according to Locke.

122. The ambiguity of his position will become clearer if we resort

to his favourite ‘instances in gold.’ The proposition, ‘all gold is

soluble in aqua regia,’ is certainly true, if such solubility is

included in the complex idea which the word ‘gold’ stands for, and

if such inclusion is all that the proposition purports to state. It

is equally certain and equally trifling with the proposition, ‘a

centaur is four-footed.’ But, in fact, as a proposition concerning

substance, it purports to state more than this, viz. that a ‘body

whose complex idea is made up of yellow, very weighty, ductile,

fusible, and fixed,’ is always soluble in aqua regia. In other words,

it states the invariable co-existence in a body of the complex idea,

‘solubility in aqua regia,’ with the group of ideas indicated by

‘gold.’ Thus understood--as instructive or synthetical--it has not

the certainty which would belong to it if it were ‘trifling,’ or

analytical, ‘since we can never, from the consideration of the ideas

themselves, with certainty affirm’ their co-existence (Book IV. chap.

vi. sec 9). If we see the solution actually going on, or can recall

the sight of it by memory, we can affirm its co-existence with the

ideas in question in that ‘bare instance;’ and thus, on the principle

that ‘whatever ideas have once been united in nature may be so united

again’ (Book IV. chap. iv. sec. 12), infer a capacity of co-existence

between the ideas, but that is all. ‘Constant observation may assist

our judgments in guessing’ an invariable actual co-existence (Book

IV. chap. viii. sec. 9); but beyond guessing we cannot get. If our

instructive proposition concerning co-existence is to be general

it must remain problematical. It is otherwise with mathematical

propositions. ‘If the three angles of a triangle were once equal to

two right angles, it is certain that they always will be so;’ but

only because such a proposition concerns merely ‘the habitudes and

relations of ideas.’ ‘If the perception that the same ideas will

eternally have the same habitudes and relations be not a sufficient

ground of knowledge, there could be no knowledge of general

propositions in mathematics; for no mathematical demonstration

could be other than particular: and when a man had demonstrated any

proposition concerning one triangle and circle, his knowledge would

not reach beyond that particular diagram’ (Book IV. chap. i. sec. 9).

Not the knowledge which is now supposed to be got by induction. Yet

more than Locke was entitled to suppose it could give.

123. To a reader, fresh from our popular treatises on Logic, such

language would probably at first present no difficulty. He would

merely lament that Locke, as a successor of Bacon, was not better

acquainted with the ‘Inductive methods,’ and thus did not understand

how an observation of co-existence in the bare instance, if the

instance be of the right sort, may warrant a universal affirmation.

Or he may take the other side, and regard Locke’s restriction upon

general certainty as conveying, not any doubt as to the validity

of the inference from an observed case to all cases where the

conditions are ascertainably the same, but a true sense of the

difficulty of ascertaining in any other case that the conditions

are the same. On looking closer, however, he will see that, so far

from Locke’s doctrine legitimately allowing of such an adaptation

to the exigencies of science, it is inconsistent with itself in

admitting the reality of most of the conditions in the case supposed

to be observed, and thus in allowing the real truth even of the

singular proposition. This purports to state, according to Locke’s

terminology, that certain ‘ideas’ do now or did once co-exist in a

body. But the ideas, thus stated to co-exist, according to Locke’s

doctrine that real existence is only testified to by actual present

sensation, differ from each other as that which _really_ exists

from that which does not. In the particular experiment of gold

being solved in aqua regia, from the complex idea of solubility an

indefinite deduction would have to be made for qualification by ideas

retained in the understanding before we could reach the present

sensation; and not only so, but the group of ideas indicated by

‘gold,’ to whose co-existence with solubility the experiment is said

to testify, as Locke himself says, form merely a nominal essence,

while the body to which we ascribe this essence is something which we

‘accustom ourselves to suppose,’ not any ‘parcel of matter’ having

a real existence in nature. [1] In asserting the co-existence of

the ideas forming such a nominal essence with the actual sensation

supposed to be given in the experiment, we change the meaning of

‘existence,’ between the beginning and end of the assertion, from

that according to which all ideas exist to that according to which

existence has no ‘connexion with any other of our ideas but those of

ourselves and God,’ but is testified to by present sensation. [2]

This paralogism escapes Locke just as his equivocal use of the term

‘idea’ escapes him. The distinction, fixed in Hume’s terminology as

that between impression and idea, forces itself upon him, as we have

seen, in the Fourth book of the Essay, where the whole doctrine of

real existence turns upon it, but alongside of it survives the notion

that ideas, though ‘in the mind’ and forming a nominal essence, are

yet, if rightly taken from things, ectypes of reality. Thus he does

not see that the co-existence of ideas, to which the particular

experiment, as he describes it, testifies, is nothing else than the

co-existence of an event with a conception--of that which is in a

particular time, and (according to him) only for that reason real,

with that which is not in time at all but is an unreal abstraction

of the mind’s making. [3] The reality given in the actual sensation

cannot, as a matter of fact, be discovered to have a necessary

connexion with the ideas that form the nominal essence, and therefore

cannot be asserted universally to co-exist with them; but with better

faculties, he thinks, the discovery might be made (Book IV. chap.

iii. sec. 16). It does not to him imply such a contradiction as it

must have done if he had steadily kept in view his doctrine that of

particular (_i.e._ real) existence our ‘knowledge’ is not properly

knowledge at all, but simply sensation--such a contradiction as was

to Hume involved in the notion of deducing a matter of fact.

[1] See above, paragraphs 35, 94, &c.

[2] See above, paragraph 30 and the following.

[3] See above, paragraphs 45, 80, 85, 97.

With Locke mathematical truths, though ideal, true also of nature.

124. It results that those followers of Locke, who hold the

distinction between propositions of mathematical certainty and those

concerning real existence to be one rather of degree than of kind,

though they have the express words of their master against them, can

find much in his way of thinking on their side. This, however, does

not mean that he in any case drops the antithesis between matters of

fact and relations of ideas in favour of matters of fact, so as to

admit that mathematical propositions concern matters of fact, but

that he sometimes drops it in favour of relations of ideas, so as

to represent real existence as consisting in such relations. If the

matter of fact, or real existence, is to be found only in the event

constituted or reported by present feeling, such a relation of ideas,

by no manner of means reducible to an event, as the mathematical

proposition states, can have no sort of connection with it. But if

real existence is such that the relations of ideas, called primary

qualities of matter, constitute it, and the qualities included in our

nominal essences are its copies or effects, then, as on the one side

our complex ideas of substances only fail of reality through want of

fulness, or through mistakes in the process by which they are ‘taken

from things,’ so, on the other side, the mental truth of mathematical

propositions need only fail to be real because the ideas, whose

relations they state, are considered in abstraction from conditions

which qualify them in real existence. ‘If it is true of the idea of

a triangle that its three angles equal two right ones, it is true

also of a triangle, wherever it really exists’ (Book IV. chap. iv.

sec. 6). There is, then, no incompatibility between the idea and

real existence. Mathematical ideas might fairly be reckoned, like

those of substances, to be taken from real existence; but though,

like these, inadequate to its complexity, to be saved from the

necessary infirmities which attach to ideas of substances because not

considered as so taken, but merely as in the mind. There is language

about mathematics in Locke that may be interpreted in this direction,

though his most explicit statements are on the other side. It is not

our business to adjust them, but merely to point out the opposite

tendencies between which a clear-sighted operator on the material

given by Locke would find that he had to choose.

Two lines of thought in Locke, between which a follower would have to

choose.

125. On the one hand there is the identification of real existence

with the momentary sensible event. This view, of which the proper

result is the exclusion of predication concerning real existence

altogether, appears in Locke’s restriction of such predication to the

singular proposition, and in his converse assertion that propositions

of mathematical certainty ‘concern not existence’ (Book IV. chap.

iv. sec. 8). The embarrassment resulting from such a doctrine is

that it leads round to the admission of the originativeness of

thought and of the reality of its originations, with the denial of

which it starts. [1] It leads Locke himself along a track, which his

later followers scarcely seem to have noticed, when he treats the

‘never enough to be admired discoveries of Mr. Newton’ as having to

do merely with the relations of ideas in distinction from things,

and looks for a true extension of knowledge--neither in syllogism

which can yield no instructive, nor in experiment which can yield no

general, certainty--but only in a further process of ‘singling out

and laying in order intermediate ideas,’ which are ‘real as well as

nominal essences of their species,’ because they have no reference

to archetypes elsewhere than in the mind (Book IV. chap. vii. sec.

11, and Book IV. chap. xii. sec. 7). On the other hand there is the

notion that ideas, without distinction between ‘actual sensation’

and ‘idea in the mind,’ are taken from permanent things, and are

real if correctly so taken. From this it results that propositions,

universally true as representing a necessary relation between ideas

of primary qualities, are true also of real existence; and that an

extension of such real certainty through the discovery of a necessary

connexion between ideas of primary and those of secondary qualities,

though scarcely to be hoped for, has no inherent impossibility. It

is this notion, again, that unwittingly gives even that limited

significance to the particular experiment which Locke assigns to it,

as indicating a co-existence between ideas present as sensations

and those which can only be regarded as in the mind. Nor is it the

intrinsic import so much as the expression of this notion that is

altered when Locke substitutes an order of nature for substance

as that in which the ideas co-exist. In his Fourth Book he so far

departs from the doctrine implied in his chapters on the reality and

adequacy of ideas and on the names of substances, as to treat the

notion of several single subjects in which ideas co-exist (which he

still holds to be the proper notion of substances), as a fiction

of thought. There are no such single subjects. What we deem so are

really ‘retainers to other parts of nature.’ ‘Their observable

qualities, actions, and powers are owing to something without them;

and there is not so complete and perfect a part that we know of

nature, which does not owe the being it has, and the excellencies

of it, to its neighbours’ (Book IV. chap. vi. sec. 11). As thus

conceived of, the ‘objective order’ which our experience represents

is doubtless other than that collection of fixed separate ‘things,’

implied in the language about substances which Locke found in vogue,

but it remains an objective order still--an order of ‘qualities,

actions, and powers’ which no multitude of sensible events could

constitute, but apart from which no sensible event could have such

significance as to render even a singular proposition of real truth

possible.

[1] See above, paragraph 117, sub. fin.

Transition to doctrine of God and the soul.

126. It remains to inquire how, with Locke, the ideas of self and

God escape subjection to those solvents of reality which, with

more or less of consistency and consciousness, he applied to the

conceptions on which the science of nature rests. Such an enquiry

forms the natural transition to the next stage in the history of his

philosophy. It was Berkeley’s practical interest in these ideas that

held him back from a development of his master’s principles, in which

he would have anticipated Hume, and finally brought him to attach

that other meaning to the ‘new way of ideas’ faintly adumbrated

in the later sections of his ‘Siris,’ which gives to Reason the

functions that Locke had assigned to Sense.

Thinking substance--source of the same ideas as outer substance.

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