a quality of ‘tangibility’ or muscular effort we merely change the
difficulty. The question as to its relation to such feelings will be
simply a repetition of that, put in the text, as to its relation to
the feeling of colour.
Hume equivocates by putting ‘coloured points’ for colour.
243. If we look to the detailed account which Hume gives of the
relation between extension and colour, we find that he avoids the
appearance of making one feeling a quality of another, by in fact
substituting for colour a superficies of coloured points, in which
it is very easy to find extension as a quality because it already
is extension as an object. To speak of extension, though a feeling,
as made up of parts is just as legitimate or illegitimate as to
speak of the feeling of colour being made up of coloured points. The
legitimacy of this once admitted, there remains, indeed, a logical
question as to how it is that a quality should be spoken of in terms
that seem proper to a substance--as is done when it is said to
consist of parts--and yet, again, should be pronounced a relation
of these parts; but to one who professed to merge all logical
distinctions in the indifference of simple feeling, such a question
could have no recognised meaning. It is, then, upon the question
whether, according to Hume’s doctrine of perception, the perception
of an object made up of coloured points may be used interchangeably
with the perception of colour, that the consistency of his doctrine
of extension must finally be tried.
244. The detailed account is to the following effect:--‘Upon opening
my eyes and turning them to the surrounding objects, I perceive many
visible bodies; and upon shutting them again and considering the
distance betwixt these bodies, I acquire the idea of extension.’
From what impression, Hume proceeds to ask, is this idea derived?
‘Internal impressions’ being excluded, ‘there remain nothing but the
senses which can convey to us this original impression.’ ... ‘The
table before me is alone sufficient by its view to give me the idea
of extension. This idea, then, is borrowed from and represents some
impression which this moment appears to the senses. But my senses
convey to me only the impressions of coloured points, disposed in a
certain manner. ... We may conclude that the idea of extension is
nothing but a copy of these coloured points and of the manner of
their appearance.’ [1]
[1] Pp. 340 and 341. [Book I, part II., sec. III.]
Can a ‘disposition of coloured points’ be an impression?
245. If the first sentence of the above had been found by Hume in
an author whom he was criticising, he would scarcely have been
slow to pronounce it tautological. As it stands, it simply tells
us that having seen things extended we consider their extension,
and upon considering it acquire an idea of it. It is a fair sample
enough of those ‘natural histories’ of the soul in vogue among us,
which by the help of a varied nomenclature seem able to explain a
supposed later state of consciousness as the result of a supposed
earlier one, because the terms in which the earlier is described
in effect assume the later. It may be said, however, that it is
only by a misinterpretation of a carelessly written sentence that
Hume can be represented as deriving the idea of extension from the
consideration of distance; that, as the sequel shows, he regarded the
‘consideration’ and the ‘idea’ in question as equivalent, and derived
from the same impression of sense. It is undoubtedly upon his account
of this impression that his doctrine of extension depends. It is
described as ‘an impression of coloured points disposed in a certain
manner.’ To it the idea of extension is related simply as a copy;
which, we have seen, properly means with Hume, as a feeling in a less
lively stage is related to the same feeling in a more lively stage.
It is itself, we must note, the _impression_ of extension; and it is
an impression of sense, about which, accordingly, no further question
can properly be raised. Hume, indeed, allows himself to speak as
if it were included in a ‘perception of visible bodies’ other than
itself; just as in the passage from the fourth book previously
examined, he speaks as if the perception, called extension, were a
quality of some other perception. This we must regard as an exercise
of the privilege which he claims of ‘speaking with the vulgar while
he thought with the learned;’ since, according to him, ‘visible
body,’ in any other sense than that of the impression of coloured
points, is properly a name for a ‘propensity to feign’ resulting from
a process posterior to all impressions of sense. The question remains
whether, in speaking of an impression as one of ‘coloured points
disposed in a certain manner,’ he is not introducing a ‘fiction
of thought’ into the impression just as much as in calling it a
‘perception of body.’
The points must be themselves impressions, and therefore not
co-existent.
246. An impression, we know, can, according to Hume, never be _of_ an
object in the sense of involving a reference to anything other than
itself. When one is said, then, to be _of_ coloured points, &c., this
can only mean that itself _is_, or consists of, such points. Thus the
question we have to answer is only a more definite form of the one
previously put, Can a feeling consist of parts? In answering it we
must remember that the parts, here supposed to be coloured points,
must, according to Hume’s doctrine, be themselves impressions or they
are nothing. Consistently with this he speaks of extension as ‘a
compound impression, consisting of parts or lesser impressions, that
are indivisible to the eye or feeling, and may be called impressions
of atoms or corpuscles, endowed with colour and solidity.’ [1] Now,
unless we suppose that a multitude of feelings of one and the same
sense can be present together, these ‘lesser impressions’ must follow
each other and precede the ‘compound impression.’ That is to say,
none of the parts of which extension consists will be in existence
at the same time, and all will have ceased to exist before extension
itself comes into being. Can we, then, adopt the alternative
supposition that a multitude of feelings of one and the same sense
can be present together? In answering this question according to
Hume’s premisses we may not help ourselves by saying that in a case
of vision there really are impressions on different parts of the
retina. To say that it _really_ is so, is to say that it is so for
the _thinking_ consciousness--for a consciousness that distinguishes
between what it feels and what it knows. To a man, as simply seeing
and while he sees, his sight is not an impression on the retina at
all, much less a combination of impressions on different parts of
the retina. It is so for him only as thinking on the organs of his
sight; or, if we like, as ‘seeing’ them in another, but ‘seeing’ them
in a way determined by sundry suppositions (bodies, rays, and the
like) which are not feelings, and therefore with Hume not possible
‘perceptions,’ at all. But it is the impression of sight, as it would
be for one simply seeing and while he sees, undetermined by reference
to anything other than itself, whether subject or object--an
impression as it would be for a merely feeling consciousness or (in
Hume’s language) ‘on the same footing with pain and pleasure’--that
we have to do with when, from Hume’s point of view, we ask whether a
multitude of such impressions can be present at once, _i.e._ as one
impression.
[1] P. 345 [Book I, part II., sec. IV.]
A ‘compound impression’ excluded by Hume’s doctrine of time.
247. If this question had been brought home to Hume, he could
scarcely have avoided the admission that to answer it affirmatively
involved just as much of a contradiction as that which he recognises
between the ‘interrupted’ and ‘continuous’ existence of objects;
[1] and just as in the latter case he gets over the contradiction
by taking the interrupted existence, because the datum of sense,
to be the reality, and the continued existence to be a belief
resulting from ‘propensities to feign,’ so in the case before us
he must have taken the multiplicity of successive impressions to
be the reality, and their co-existence as related parts to be a
figure of speech, which he must account for as best he could. As
it is, he so plays fast and loose with the meaning of ‘impression’
as to hide the contradiction which is involved in the notion of a
‘compound impression’ if impression is interpreted as feeling--the
contradiction, namely, that a single feeling should he felt to be
manifold--and in consequence loses the chance of being brought to
that truer interpretation of the compound impression, as the thought
of an object under relations, which a more honest trial of its
reduction to feeling might have shown to be necessary. To convict so
skilful a writer of a contradiction in terms can never be an easy
task. He does not in so many words tell us that all impressions of
sight must be successive, but he does tell us that ‘the impressions
of touch,’ which, indifferently with those of sight, he holds to
constitute the compound impression of extension, ‘change every moment
upon us.’ [2] And in the immediate sequel of the passage where he
has made out extension to be a compound of co-existent impressions,
he derives the idea of time ‘from the succession of our perceptions
_of every kind_, ideas as well as impressions, and impressions of
reflection as well as of sensation.’ The parts of time, he goes on to
say, cannot be co-existent; and, since ‘time itself is nothing but
different ideas and impressions succeeding each other,’ these parts,
we must conclude, are those ‘perceptions of every kind’ from which
the idea of time is derived. [3] It is only, in fact, by availing
himself of the distinction, which he yet expressly rejects, between
the impression and its object, that he disguises the contradiction in
terms of first pronouncing certain impressions, as parts of space,
co-existent, and then pronouncing all impressions, as parts of time,
successive. A statement that ‘as from the coexistence of visual, and
also of tactual, perceptions we receive the idea of extension, so
from the succession of perceptions of every kind we form the idea
of time,’ would arouse the suspicion of the most casual reader;
while Hume’s version of the same,--‘as ’tis from the disposition of
visible and tangible objects we receive the idea of space, so from
the succession of ideas and impressions we form the idea of time’
[4]--has the full ring of empirical plausibility.
[1] P. 483 and following, and p. 486 [Book I, part IV., sec. II.]
[2] P. 516 [Book I, part IV., sec. IV.].
[3] Pp. 342, 343 [Book I, part II., sec. III.].
[4] P. 342 [Book I, part II., sec. III.]
The fact that colours mix, not to the purpose.
248. This plausibility depends chiefly on our reading into Hume’s
doctrine a physical theory which, as implying a distinction between
feeling and its real but unfelt cause, is strictly incompatible with
it. Is it not an undoubted fact, the reader asks, that two colours
may combine to produce a third different from both--that red and
yellow, for instance, together produce orange? Is not this already an
instance of a compound impression? Why may not a like composition of
unextended impressions of colour constitute an impression different
from any one of the component impressions, viz. extended colour?
A moment’s consideration, however, will show that no one has a
conscious sensation at once of red and yellow, and of orange as a
compound of the two. The elements which combine to produce the colour
called orange are not--as they ought to be if it is to be a case of
compound impression in Hume’s sense--feelings of the person who sees
the orange colour, but certain known causes of feeling, confused in
language with the feelings, which separately they might produce,
but which in fact they do not produce when they combine to give the
sensation of orange; and to such causes of feeling, which are not
themselves feelings, Hume properly can have nothing to say.
How Hume avoids appearance of identifying space with colour, and
accounts for the abstraction of space.
249. So far we have been considering the composition of impressions
generally, without special reference to extension. The contradiction
pointed out arises from the confusion between impressions as felt
and impressions as thought of; colour, between feelings as they
are in themselves, presented successively in time, and feelings as
determined by relation to the thinking subject, which takes them out
of the flux of time and converts them into members of a permanent
whole. It is in this form that the confusion is most apt to elude us.
When the conceived object is one of which the qualities can really
be felt, _e.g._ colour, we readily forget that a felt quality is no
longer simply a feeling. But the case is different when the object
is one, like extension, which forces on us the question whether its
qualities can be felt, or presented in feeling, at all. A compound
of impressions of colour, to adopt Hume’s phraseology, even if such
composition were possible, would still be nothing else than an
impression of colour. In more accurate language, the conception,
which results from the action of thought upon feelings of colour,
can only be a conception of colour. Is extension, then, the same as
colour? To say that it was would imply that geometry was a science
of colour; and Hume, though ready enough to outrage ‘Metaphysics and
School Divinity,’ always stops reverently short of direct offence
to the mathematical sciences. As has been said above, of the three
main questions about the idea of extension which his doctrine
raises--Is it itself extended? Is it possible without reference to
something other than a possible impression? Is it the same as the
idea of colour or tangibility?--the last is the only one which he can
scarcely even profess to answer in the affirmative. [1] Even when he
has gone so far as to speak of the parts of a perception, a sound
instinct compels him, instead of identifying the perception directly
with extension, to speak of it as ‘affording through the situation
of its parts the notion of’ extension. [2] In like manner, when he
has asserted extension to be a compound of impressions, he avoids
the proper consequence of the assertion by speaking of the component
impressions as those, not of colour but, of coloured points, ‘atoms
or corpuscles endowed with colour and solidity;’ and, again, does not
call extension the compound of these simply, but the compound of them
as ‘disposed in a certain manner.’ When the idea which is a copy of
this impression has to be spoken of, the expression is varied again.
It is an ‘idea of the coloured points _and of the manner of their
appearance_,’ or of their ‘disposition.’ The disposition of the parts
having been thus virtually distinguished from their colour, it is
easy to suppose that, finding a likeness in the disposition of points
under every unlikeness of their colour, ‘we omit the peculiarities
of colour, as far as possible, and found an abstract idea merely on
that disposition of points, or manner of appearance, in which they
agree. Nay, even when the resemblance is carried beyond the objects
of one sense, and the impressions of touch are found to be similar
to those of sight in the disposition of their parts, this does not
hinder the abstract idea from representing both on account of their
resemblance’. [3]
[1] Above, paragraph 233. Though, as we shall see, he does so in one
passage.
[2] Above, paragraph 235.
[3] P. 341 [Book I, part II., sec. III.]
In so doing, he implies that space is a relation, and a relation
which is not a possible impression.
250. If words have any meaning, the above must imply that the
disposition of points is at least a different idea from either colour
or tangibility, however impossible it may be for us to experience
it without one or other of the latter. Nor can we suppose that
this impression, other than colour, is one that first results from
the composition of colours, even if we admit that such composition
could yield a result different from colour. According to Hume,
the components of the compound impression are already impressions
of coloured ‘points, atoms, or corpuscles,’ and such points imply
just that limitation by mutual externality, which is already the
disposition in question. Is this ‘disposition,’ then, an impression
of sensation? If so, ‘through which of the senses is it received? If
it be perceived by the eyes it must be a colour,’ &c. &c.; [1] but
from colour, the impression with which Hume would have identified it
if he could, he yet finds himself obliged virtually to distinguish
it. It is a relation, and not even one of those relations, such as
resemblance, which in Hume’s language, ‘depending on the nature
of the impressions related,’ [2] may plausibly be reckoned to
be themselves impressions. The ‘disposition’ of parts and their
‘situation’ he uses interchangeably, and the situation of impressions
he expressly opposes to their ‘nature’ [3]--that nature in respect
of which all impressions, call them what we like, are ‘originally
on the same footing’ with pain and pleasure. Consistently with this
he pronounces the ‘external position’ of objects--their position as
bodies external to each other and to our body--to be no datum of
sense, no impression or idea, at all. [4] Our belief in it has to
be accounted for as a complex result of ‘propensities to feign.’
How, then, can there be an impression of that which does not belong
to the nature of any impression? What difference is there between
‘bodies’ and ‘corpuscles endowed with colour and solidity,’ that the
outwardness of the latter to each other--also called their ‘distance’
from each, other [5]--should be an impression, while it is admitted
that the same relation between ‘bodies’ cannot be so?
[1] Above, paragraph 208.
[2] P. 372 [Book I, part III., sec. I.], ‘Philosophical relations
may be divided into two classes: into such as depend entirely on the
ideas which we compare together; and such as may be changed without
any change in the ideas. ... The relations of contiguity and distance
between two objects may be changed without any change in the objects
themselves or their ideas.’
[3] P. 480. [Book I, part IV., sec. II.] ‘When we doubt whether
sensations present themselves as distinct objects or as mere
impressions, the difficulty is not concerning their nature, but
concerning their relations and situation.’
[4] P. 481. [Book I, part IV., sec. II.] In there showing that the
senses alone cannot convince us of the external existence of body,
he remarks that ‘sounds, tastes, and smells appear not to have any
existence in extension;’ and (p. 483) [ibid] ‘as far as the senses
are judges, all perceptions are the same in the manner of their
existence.’ Therefore perceptions of sight cannot have ‘an existence
in extension’ any more than ‘sounds, tastes, and smells;’ and if so,
how can ‘existence in extension’ be a perception?
[5] Above, paragraphs 235 and 244.
No logical alternative between identifying space with colour, and
admitting an idea not copied from an impression.
251. To have plainly admitted that it was not an impression must
have compelled Hume either to discard the ‘abstract idea’ with which
geometry deals, or to admit the possibility of ideas other than
‘fainter impressions.’ It is a principle on which he insists with
much emphasis and repetition, that whatever ‘objects,’ ‘impressions,’
or ‘ideas’ are distinguishable are also separable. [1] Now if there
is an abstract idea of extension, it can scarcely be other than
distinguishable, and consequently (according to Hume’s account of
the relation of idea to impression) derived from a distinguishable
and therefore separable impression. It would seem then that Hume
cannot escape conviction of one of two inconsistencies; either that
of supposing a separate impression of extension, which yet is not
of the nature of any assignable sensation; or that of supposing an
abstract idea of it in the absence of any such impression. We shall
find that he does not directly face either horn of the dilemma, but
evades both of them. He admits that ‘the ideas of space and time
are no separate and distinct ideas, but merely those of the manner
or order in which objects’ (_sc._ impressions) ‘exist’. [2] In the
Fourth Book, where the equivalence of impression to feeling is more
consistently carried out, the fact that what is commonly reckoned an
impression is really a judgment about the ‘manner of existence,’ as
opposed to the ‘nature,’ of impressions, is taken as sufficient proof
that it is no impression at all; and if not an impression, therefore
not an idea. [3] He thus involuntarily recognized the true difference
between feeling and thought, between the mere occurrence of feelings
and the presentation of that occurrence by the self-conscious subject
to itself; and, if only he had known what he was about in the
recognition, might have anticipated Kant’s distinction between the
matter and form of sensation. In the Second Book, however, he will
neither say explicitly that space is an impression of colour or a
compound of colours--that would be to extinguish geometry; nor yet
that it is impression of sense separate from that of colour--that
would lay him open to the retort that he was virtually introducing
a sixth sense; nor on the other hand will he boldly avow of it, as
he afterwards does of body, that it is a fiction. He denies that it
is a separate impression, so far as that is necessary for avoiding
the challenge to specify the sense through which it is received;
he distinguishes it from a mere impression of sight, when it is
necessary to avoid its simple identification with colour. By speaking
of it as ‘the manner in which objects exist’--so long as he is not
confronted with the declarations of the Fourth Book or with the
question how, the objects being impressions, their order of existence
can be at once that of succession in time and of co-existence in
space--he gains the credit for it of being a datum of sight, yet
so far distinct from colour as to be a possible ‘foundation for an
abstract idea,’ representative also of objects not coloured at all
but tangible. At the same time, if pressed with the question how it
could be an impression of sight and yet not interchangeable with
colour, he could put off the questioner by reminding him that he
never made it a ‘separate or distinct impression, but one of the
manner in which objects exist.’
[1] Pp. 319, 326, 332, 335, 518. [Book I, part I., sec. IV and VII,
part II, sec. I, and part IV., sec. V.]
[2] P. 346. [Book I, part II., sec. IV.]
[3] P. 480. [Book I, part IV., sec. II.]
In his account of the idea as _abstract_, Hume really introduces
distinction between feeling and conception;