129. This attempt to present Locke’s doctrine of the relation between the mind and the world, as it would be without phraseological disguises, must not be ascribed to any polemical interest in making a great writer seem to talk nonsense, The greatest writer must fall into confusions when he brings under the conceptions of cause and substance the self-conscious thought which is their source; and nothing else than this is involved in Locke’s avowed enterprise of knowing that which renders knowledge possible as he might know any other object. The enterprise naturally falls into two parts, corresponding to that distinction of subject and object which self-consciousness involves. Hitherto we have been dealing with it on the objective side—with the attempt to know knowledge as a result of experience received through the senses—and have found the supposed source of thought already charged with its creations; with the relations of inner and outer, of substance and attribute, of cause and effect, of appearance and reality. The supposed ‘outward’ turns out to have its outwardness constituted by thought, and thus to be inward. The ‘outer sense’ is only an outer sense at all so far as feelings, by themselves neither outward nor inward, are by the mind referred to a thing or cause which ‘the mind supposes;’ and only thus have its reports a prerogative of reality over the ‘fantasies,’ supposed merely of the mind. Meanwhile, unable to ignore the subjective side of self-consciousness, Locke has to put an inward experience as a separate, but co-ordinate, source of knowledge alongside of the outer. But this inward experience, simply as a succession of feelings, does not differ from the outer: it only so differs as referred to that very ‘thinking thing,’ called the mind, which by its supposition of causal substance has converted feeling into an experience of an outer thing. ‘Mind’ thus, by the relations which it ‘invents,’ constitutes both the inner and outer, and yet is treated as itself the inner ‘substratum which it accustoms itself to suppose.’ It thus becomes the creature of its own suppositions. Nor is this all. This, indeed, is no more than the fate which it must suffer at the hands of every philosopher who, in Kantian language, brings the source of the Categories under the Categories. But with Locke the constitution of the outer world by mental supposition, however uniformly implied, is always ignored; and thus mind, as the inward substance, is not only the creature of its own suppositions, but stands over against a real existence, of which the reality is held to consist just in its being the opposite of all such suppositions: while, after all, the effect of these mutually exclusive causes is one and the same experience, one and the same system of sequent and co-existent ideas.
To get rid of the inner source of ideas in favour of the outer would be false to Locke.
130. Is it then a case of joint-effect? Do the outer and inner substances combine, like mechanical forces, to produce the psychical result? Against such a supposition a follower of Locke would find not only the language of his master, with whom perception appears indifferently as the result of the outer or inner cause, but the inherent impossibility of analysing the effect into separate elements. The ‘Law of Parsimony,’ then, will dictate to him that one or other of the causes must be dispensed with; nor, so long as he takes Locke’s identification of the outward with the real for granted, will he have much doubt as to which of the two must go. To get rid of the causality of mind, however, though it might not be untrue to the tendency of Locke, would be to lose sight of his essential merit as a formulator of what everyone thinks, which is that, at whatever cost of confusion or contradiction, he at least formulates it fully. In him the ‘Dialectic,’ which popular belief implicitly involves, goes on under our eyes. If the primacy of self-conscious thought is never recognized, if it remains the victim of its own misunderstood creations, there is at least no attempt to disguise the unrest which attaches to it in this self-imposed subjection.
The mind, which Locke opposes to matter, perpetually shifting.
131. We have already noticed how the inner ‘tablet,’ on which the outer thing is supposed to act, is with Locke perpetually receding. [1] It is first the brain, to which the ‘motion of the outward parts’ must be continued in order to constitute sensation (Book II. chap. ix. sec. 3). Then perception is distinguished from sensation, and the brain itself, as the subject of sensation, becomes the outward in contrast with the understanding as the subject of perception. [2] Then perception, from being simply a reception, is converted into an ‘operation,’ and thus into an efficient of ideas. The ‘understanding’ itself, as perceptive, is now the outward which makes on the ‘mind,’ as the inner ‘tablet,’ that impression of its own operation in perception which is called an idea of reflection. [3] Nor does the regressive process—the process of finding a mind within the mind—stop here, though the distinction of inner and outer is not any further so explicitly employed in it. From mind, as receptive of, and operative about, ideas, i.e. consciousness, is distinguished mind as the ‘substance within us’ of which consciousness is an ‘operation’ that it sometimes exercises, sometimes (e.g. when it sleeps) does not (Book II. chap. i. secs. 10-12); and from this thinking substance again is distinguished the man who ‘finds it in himself and carries it about with him in a coach or on horseback (Book II. chap, xxiii. sec. 20)—the person, ‘consisting of soul and body,’ who is prone to sleep and in sound sleep is unconscious, but whose personal identity strangely consists in sameness of consciousness, sameness of an occasional operation of part of himself. [3]
[1] See above, paragraph 14.
[2] Book II., chap. i. sec. 23. ‘Sensation is such an impression made in some part of the body, as produces some perception in the understanding.’
[3] Locke speaks indifferently of the mind impressing the understanding, and of the understanding impressing the mind, with ideas of reflection, but as he specially defines ‘understanding’ as the ‘perceptive power’ (Book II. chap. xxi. sec. 25.), I have written as above.
[4] Cf. II. chap. i. secs. 11 and 14, with II. chap, xxvii. sec. 9. It is difficult to see what ingenuity could reconcile the doctrine stated in Book II. chap. xxvii. sec. 9, that personal identity is identity of consciousness, with the doctrine implied in Book II. chap. i. sec. 11, that the waking Socrates is the same person with Socrates asleep, i.e. (according to Locke) not conscious at all.
Two ways out of such difficulties. ‘Matter’ and ‘mind’ have the same source in self-consciousness.