in habit, suffers from a weakness quite as fatal as that which he
supposes to attach to it if accounted for as the work of reason.
‘The work of reason’ to a follower of Locke meant either the mediate
perception of likeness between ideas, which the discovery of cause or
effect cannot be; or else syllogism, of which Locke had shown once
for all that it could yield no ‘instructive propositions.’ But if an
idea arrived at by that process could be neither new nor real--not
new, because we must have been familiar with it before we put it
into the compound idea from which we ‘deduce’ it; not real, because
it has not the liveliness either of sensation or of memory--the
idea inferred according to Hume’s process, however real with the
reality of liveliness, is certainly not new. ‘If this means’ (the
modern logician may perhaps reply), ‘that according to Hume no new
phenomenon can be given by inference, he was quite right in thinking
so. If the object of inference were a separate phenomenon, it would
be quite true that it must have been repeatedly perceived before it
could be inferred, and that thus inference would be nugatory. But
inference is in fact not to such an object, but to a uniform relation
of certain phenomena in the way of co-existence and sequence; and
what Hume may be presumed to mean is not that every such relation
must have been perceived before it can be inferred, much less that
it must have been perceived so constantly that an appearance of the
one phenomenon causes instinctive expectation of the other, but _(a)_
that the phenomena themselves must have been given by immediate
perception, and _(b)_ that the conception of a law of causation, in
virtue of which a uniformity of relation between them is inferred
from a single instance of it, is itself the result of an “inductio
per enumerationem simplicem,” of the accumulated experience of
generations that the same sequents follow the same antecedents.’
Nor does this merely mean that it cannot constitute new phenomena,
while it can prove relations, previously unknown, between phenomena.
Such a distinction inadmissible with Hume.
334. At the point which our discussion has reached, few words should
be wanted to show that thus to interpret Hume is to read into him
an essentially alien theory, which has doubtless grown out of his,
but only by a process of adaptation which it needs a principle the
opposite of his to justify. Hume, according to his own profession,
knows of no objects but impressions and ideas--feelings stronger or
more faint--of no reality which it needs thought, as distinct from
feeling, to constitute. But a uniform relation between phenomena
is neither impression nor idea, and can only exist for thought.
He could not therefore admit inference to such relation as to a
real existence, without a double contradiction, nor does he ever
explicitly do so. He never allows that inference is other than a
transition to a certain sort of feeling, or that it is other than
the work of imagination, the weakened sense, as enlivened by custom
to a degree that puts it _almost_ on a level with sense; which
implies that in every case of inference the inferred object is
_not_ a uniform relation--for how can there be an image of uniform
relation?--and that it _is_ something which has been repeatedly
and without exception perceived to follow another before it can be
inferred. Even when in violation of his principle he has admitted
a ‘system of memory’--a system of things which have been felt, but
which are not feelings, stronger or fainter, and which are what they
are only through relation--he still in effect, as we have seen, makes
the ‘system of judgment,’ which he speaks of as inferred from it,
only the double of it. To suppose that, on the strength of a general
inference, itself the result of habit, in regard to the uniformity
of nature, particular inferences may be made which shall be other
than repetitions of a sequence already habitually repeated, is, if
there can be degrees of contradiction, even more incompatible with
Hume’s principles than to suppose such inferences without it. If
a uniformity of relation between particular phenomena is neither
impression nor idea, even less so is the system of all relations.
His distinction of probability of causes from that of chances might
seem to imply conception of nature, as determining inference.
335. There is language, however, in the chapters on ‘Probability of
Chances and of Causes,’ which at first sight might seem to warrant
the ascription of such a supposition to Hume. According to the
distinction which he inherited from Locke all inference to or from
causes or effects, since it does not consist in any comparison of the
related ideas, should be merely probable. And as such he often speaks
of it. His originality lies in his effort to explain what Locke had
named; in his treating that ‘something not joined on both sides
to, and so not showing the agreement or disagreement of, the ideas
under consideration’ which yet ‘makes me believe’, [1] definitely
as Habit. But ‘in common discourse,’ as he remarks, ‘we readily
affirm that many arguments from causation exceed probability’; [2]
the explanation being that in these cases the habit which determines
the transition from impression to idea is ‘full and perfect.’ There
has been enough past experience of the immediate sequence of the
one ‘perception’ on the other to form the habit, and there has been
no exception to it. In these cases the ‘assurance,’ though distinct
from knowledge, may be fitly styled ‘proof,’ the term ‘probability’
being confined to those in which the assurance is not complete. Hume
thus comes to use ‘probability’ as equivalent to incompleteness of
assurance, and in this sense speaks of it as ‘derived either from
imperfect experience, or from contrary causes, or from analogy’.
[3] It is derived from analogy when the present impression, which
is needed to give vivacity to the ‘related idea,’ is not perfectly
like the impressions with which the idea has been previously found
united; ‘from contrary causes,’ when there have been exceptions to
the immediate sequence or antecedence of the one perception to the
other; ‘from imperfect experience’ when, though there have been no
exceptions, there has not been enough experience of the sequence to
form a ‘full and perfect habit of transition.’ Of this last ‘species
of probability,’ Hume says that it is a kind which, ‘though it
naturally takes place before any entire proof can exist, yet no one
who is arrived at the age of maturity can any longer be acquainted
with. ’Tis true, nothing is more common than for people of the most
advanced knowledge to have attained only an imperfect experience of
many particular events; which naturally produces only an imperfect
habit and transition; but then we must consider that the mind, having
formed another observation concerning the connexion of causes and
effects, gives new force to its reasoning from that observation;
and by means of it can build an argument on one single experiment,
when duly prepared and examined. What we have found once to follow
from any object we conclude will for ever follow from it; and if
this maxim be not always built upon as certain, ’tis not for want of
a sufficient number of experiments, but because we frequently meet
with instances to the contrary’--which give rise to the other sort of
weakened assurance or probability, that from ‘contrary causes’. [4]
[1] Locke, 4, 15, 3.
[2] P. 423. [Book I, part III., sec. XI.]
[3] P. 439. [Book I, part III., sec. XIII.]
[4] Pp. 429 & 430. [Book I, part III., sec. XII.]
But this distinction he only professes to adopt in order to explain
it away.
336. There is a great difference between the meaning which the above
passage conveys when read in the light of the accepted logic of
science, and that which it conveys when interpreted consistently with
the theory in the statement of which it occurs. Whether Hume, in
writing as he does of that conclusion from a single experiment, which
our observation concerning the connexion of cause and effect enables
us to draw, understood himself to be expressing his own theory or
merely using the received language provisionally, one cannot be
sure; but it is certain that such language can only be justified by
those ‘maxims of philosophers’ which it is the purpose or effect of
his doctrine to explain away--in particular the maxims that ‘the
connexion between all causes and effects is equally necessary and
that its seeming uncertainty in some instances proceeds from the
secret opposition of contrary causes;’ and that ‘what the vulgar
call chance is but a concealed cause’. [1] These maxims represent
the notion that the law of causation is objective and universal;
that all seeming limitations to it, all ‘probable and contingent
matter,’ are the reflections of our ignorance, and exist merely _ex
parte nostrâ_. In other words, they represent the notion of that
‘continued existence distinct from our perceptions,’ which with Hume
is a phrase generated by ‘propensities to feign.’ Yet he does not
profess to reject them; nay, he handles them as if they were his own,
but after a very little of his manipulation they are so ‘translated’
that they would not know themselves. Because philosophers ‘allow
that what the vulgar call chance is nothing but a concealed cause,’
‘probability of causes’ and ‘probability of chances’ may be taken as
equivalent. But chance, as ‘merely negation of a cause,’ has been
previously explained, on the supposition that causation means a
‘perfect habit of imagination,’ to be the absence of such habit--the
state in which imagination is perfectly indifferent in regard to the
transition from a given impression to an idea, because the transition
has not been repeated often enough to form even the beginning of a
habit. Such being mere chance, ‘probability of chances’ means a state
of imagination between the perfect indifference and that perfect
habit of transition, which is ‘necessary connexion.’ ‘Probability
of causes’ is the same thing. Its strength or weakness depends
simply on the proportion between the number of experiments (‘each
experiment being a kind of chance’) in which A has been found to
immediately follow B, and the number of those in which it has not.
[2] Mere chance, probability, and causation then are equally states
of imagination. The ‘equal necessity of the connexion between all
causes and effects’ means not that any ‘law of causation pervades
the universe,’ but that, unless the habit of transition between any
feelings is ‘full and perfect,’ we do not speak of these feelings as
related in the way of cause and effect.
[1] Pp. 429 & 430. [Book I, part III., sec. XII.]
[2] Pp. 424-428, 432-434. [Book I, part III., secs. XI. and XII.]
Laws of nature are unqualified habits of expectation.
337. Interpreted consistently with this doctrine, the passage quoted
in the last paragraph but one can only mean that, when a man has
arrived at maturity, his experience of the sequence of feelings
cannot fail in quantity. He must have had experience _enough_ to form
not only a perfect habit of transition from any impression to the
idea of its usual attendant, but a habit which would act upon us even
in the case of novel events, and lead us after a single experiment
or a sequence confidently to expect its recurrence, if only the
experience had been _uniform_. It is because it has not been so,
that in many cases the habit of transition is still imperfect, and
the sequence of A on B not ‘proven,’ but ‘probable.’ The probability
then which affects the imagination of the matured man is of the sort
that arises from ‘contrary causes,’ as distinct from ‘imperfect
experience.’ This is all that the passage in question can fairly
mean. Such ‘probability’ cannot become ‘proof,’ or the ‘imperfect
habit,’ perfect, by _discovery_ of any necessary connexion or law
of causation, for the perfect habit of transition, the imagination
enlivened to the maximum by custom, _is_ the law of causation. The
formation of the habit constitutes the law: to discover it would be
to discover what does not yet exist. The incompleteness of the habit
in certain directions, the limitation of our assurance to certain
sequences as distinct from others, must be equally a limitation
to the universality of the law. It is impossible then that on the
faith of the universality of the law we should seek to extend the
range of that assurance which is identical with it. Our ‘observation
concerning the connexion of causes and effects’ merely means the sum
of our assured expectations, founded on habit, at any given time,
and that on the strength of this we should ‘prepare an experiment,’
with a view to assuring ourselves of a universal sequence from a
single instance, is as unaccountable as that, given the instance, the
assurance should follow.
Experience, according to his account of it, cannot be a parent of
knowledge.
338. The case then stands thus. In order to make the required
distinction between inference to real existence and the lively
suggestion of an idea, Hume has to graft on his theory the alien
notion of an objective system, an order of nature, represented by
ideas of memory, and on the strength of such a notion to interpret
a transition from these ideas to others, because we cannot help
making it, as an objective necessity. Of such alien notion and
interpretation he avails himself in his definition (understood as he
means it to be understood) of cause as a ‘natural relation’. [1] But
he had not the boldness of his later disciples. Though he could be
inconsistent so far, he could not be inconsistent far enough to make
his theory of inference fit the practice of natural philosophers.
Bound by his doctrine of ideas as copied from impressions, he can
give no account of inferred ideas that shall explain the extension
of knowledge beyond the expectation that we shall feel again what we
have felt already. It was not till another theory of experience was
forthcoming than that given by the philosophers who were most fond of
declaring their devotion to it, that the procedure of science could
be justified. The old philosophy, we are often truly told, had been
barren for want of contact with fact. It sought truth by a process
which really consisted in evolving the ‘connotation’ of general
names. The new birth came when the mind had learnt to leave the idols
of the tribe and cave, and to cleave solely to experience. If the
old philosophy, however, was superseded by science, science itself
required a new philosophy to answer the question. What constitutes
experience? It was in effect to answer this question that Locke
and Hume wrote, and it is the condemnation of their doctrine that,
according to it, experience is not a possible parent of science. It
is not those, we know, who cry ‘Lord, Lord!’ the loudest, that enter
into the kingdom of heaven, nor does the strongest assertion of our
dependence on experience imply a true insight into its nature. Hume
has found acceptance with men of science as the great exponent of the
doctrine that there can be no new knowledge without new experience.
It has not been noticed that with him such ‘new experience’ could
only mean a further repetition of familiar feelings, and that if it
means more to his followers, it is only because they have been less
faithful than he was to that antithesis between thought and reality
which they are not less loud in asserting.
[1] See above, paragraph 317.
His attitude towards doctrine of thinking substance.
339. From the point that our enquiry has reached, we can anticipate
the line which Hume could not but take in regard to Self and God.
His scepticism lay ready to his hand in the incompatibility between
the principles of Locke and that doctrine of ‘thinking substance,’
which Locke and Berkeley alike maintained. If the reader will revert
to the previous part of this introduction, in which that doctrine
was discussed, [1] he will find it equally a commentary upon
those sections of the ‘Treatise on Human Nature’ which deal with
‘immateriality of the soul’ and ‘personal identity.’ Substance, we
saw, alike as ‘extended’ and as ‘thinking,’ was a ‘creation of the
mind,’ yet real; something of which there was an ‘idea,’ but of which
nothing could be said but that it was not an ‘idea.’ The ‘thinking’
substance, moreover, was at a special disadvantage in contrast with
the ‘extended,’ because, in the first place, it could not, like body,
be represented as given to consciousness in the feeling of solidity,
and secondly it was not wanted. It was a mere double of the extended
substance to which, as the ‘something wherein they do subsist and
from which they do result’ our ideas had already been referred.
Having no conception, then, of Spirit or Self before him but that
of the thinking substance, of which Berkeley had confessed that
it was not a possible idea or object of an idea, Hume had only to
apply the method, by which Berkeley himself had disposed of extended
substance, to get rid of Spirit likewise. This could be done in a
sentence, [2] but having done it, Hume is at further pains to show
that immateriality, simplicity, and identity cannot be ascribed to
the soul; as if there were a soul left to which anything could be
ascribed.
[1] Above, paragraphs 127-135, 144-146, & 192.
[2] P. 517. [Book I, part IV., sec. V.]
As to Immateriality of the Soul, he plays off Locke and Berkeley
against each other, and proves Berkeley a Spinozist.
340. There were two ways of conceiving the soul as immaterial, of
which Hume was cognizant. One, current among the theologians and
ordinary Cartesians and adopted by Locke, distinguishing extension
and thought as severally divisible and indivisible, supposed
separate substances--matter and the soul--to which these attributes,
incapable of ‘local conjunction,’ severally belonged. The other,
Berkeley’s, having ostensibly reduced extended matter to a succession
of feelings, took the exclusion of all ‘matter’ to which thought
could be ‘joined’ as a proof that the soul was immaterial. Hume,
with cool ingenuity, turns each doctrine to account against the
other. From Berkeley he accepts the reduction of sensible things to
sensations. Our feelings do not represent extended objects other
than themselves; but we cannot admit this without acknowledging the
consequence, as Berkeley himself implicitly did, [1] that certain of
our impressions--those of sight and touch--are themselves extended.
What then becomes of the doctrine, that the soul must be immaterial
because thought is not extended, and cannot be joined to what is
so? Thought means the succession of impressions. Of these some,
though the smaller number, are actually extended; and those that
are not so are united to those that are by the ‘natural relations’
of resemblance and of contiguity in time of appearance, and by the
consequent relation of cause and effect. [2] The relation of local
conjunction, it is true, can only obtain between impressions which
are alike extended. The ascription of it to such as are unextended
arises from the ‘propensity in human nature, when objects are united
by any relation, to add some new relation in order to complete the
union’. [3] This admission, however, can yield no triumph to those
who hold that thought can only be joined to a ‘simple and indivisible
substance.’ If the existence of unextended impressions requires the
supposition of a thinking substance ‘simple and indivisible,’ the
existence of extended ones must equally imply a thinking substance
that has all the properties of extended objects. If it is absurd
to suppose that perceptions which are unextended can belong to a
substance which is extended, it is equally absurd to suppose that
perceptions which are extended can belong to a substance that is
not so. Thus Berkeley’s criticism has indeed prevailed against the
vulgar notion of a material substance as opposed to a thinking one,
but meanwhile he is himself ‘hoist with his own petard.’ If that
thinking substance, the survival of which was the condition of his
theory serving its theological purpose, [4] is to survive at all,
it can only be as equivalent to Spinoza’s substance, in which ‘both
matter and thought were supposed to inhere.’ The universe of our
experience--‘the sun, moon, and stars; the earth, seas, plants,
animals, men, ships, houses, and other productions, either of art
or nature’--is the same universe when it is called ‘the universe of
objects or of body,’ and when it is called ‘the universe of thought,
or of impressions and ideas;’ but to hold, according to Spinoza’s
‘hideous hypothesis,’ that ‘the universe of objects or of body’
inheres in one simple uncompounded substance, is to rouse ‘a hundred
voices of scorn and detestation;’ while the same hypothesis in regard
to the ‘universe of impressions and ideas’ is treated ‘with applause
and veneration.’ It was to save God and Immortality that the ‘great
philosopher,’ who had found the true way out of the scholastic
absurdity of abstract ideas, [5] had yet clung to the ‘unintelligible
chimaera’ of thinking substance; and after all, in doing so, he fell
into a ‘true atheism,’ indistinguishable from that which had rendered
the unbelieving Jew ‘so universally infamous’. [6]
[1] See above, par. 177.
[2] Pp. 520-521. [Book I, part IV., sec. V.]
[3] P. 521. [Book I, part IV., sec. V.]
[4] See page 325. [Book I, part I., sec. VII.]
[5] See above, paragraphs 191 and foll.
[6] Pp. 523-526. [Book I, part IV., sec. V.]
Causality of spirit treated in the same way.
341. The supposition of spiritual substance being thus at once
absurd, and of a tendency the very opposite of the purpose it was
meant to serve, can anything better be said for the supposition of
a spiritual cause? It was to the representation of spirit as cause
rather than as substance, it will be remembered, that both Locke
and Berkeley trusted for the establishment of a Theism which should
not be Pantheism. [1] Locke, in his demonstration of the being of
God, trusted for proof of a first cause to the inference from that
which begins to exist to something having power to produce it, and
to the principle of necessary connexion--connexion in the way of
agreement of ideas--between cause and effect for proof that this
first cause must be immaterial, even as its effect, viz. our thought,
is. Hume’s doctrine of causation, of course, renders both sides of
the demonstration unmeaning. Inference being only the suggestion by
a feeling of the image of its ‘usual attendant,’ there can be no
inference to that which is not a possible image of an impression.
Nor, since causation merely means the constant conjunction of
impressions, and there is no such contrariety between the impression
we call ‘motion of matter’ and that we call ‘thought,’ anymore than
between any other impressions, [2] as is incompatible with their
constant conjunction, is there any reason why we should set aside the
hourly experience, which tells us that bodily motions are the cause
of thoughts and sentiments. If, however, there were that necessary
connexion between effect and cause, by which Locke sought to show the
spirituality of the first cause, it would really go to show just the
reverse of infinite power in such cause. It is from our impressions
and ideas that we are supposed to infer this cause; but in these--as
Berkeley had shown, and shown as his way of proving the existence of
God--there is no efficacy whatever. They are ‘inert.’ If then the
cause must agree with the effect, the Supreme Being, as the cause
of our impressions and ideas, must be ‘inert’ likewise. If, on the
other hand, with Berkeley we cling to the notion that there must be
efficient power somewhere, and having excluded it from the relation
of ideas to each other or of matter to ideas, find it in the direct
relation of God to ideas, we fall ‘into the grossest impieties;’
for it will follow that God ‘is the author of all our volitions and
impressions.’ [3]
[1] See above, §§ 147, 171, 193.
[2] There is no contrariety, according to Hume, except between
existence and non-existence (p. 323) [Book I, part I., sec. V.] and
as all impressions and ideas equally exist (p. 394) [Book I, part
III., sec. VII.], there can be no contrariety between any of them.
He does indeed in certain leading passages allow himself to speak
of contrariety between ideas (_e.g._ pp. 494 and 535 [Book I, part
IV., secs. II. and VI.]), which is incidental evidence that the ideas
there treated of are not so, according to his account of ideas, at
all.
[3] Pp. 529-531 [Book I, part IV., sec. V.], a commentary on the
argument here given has been in effect supplied in paragraphs
148-152, and 194.
Disposes of ‘personal’ identity by showing contradictions in Locke’s
account of it.