454 



NA TURE 



\_March 20, 1879 



— hypothesis and hypothetical inference; having no bear- 

 ing on our experience. 



What Hume really sought in philosophy was the ulti- 

 mate element, out of which all valid knowledge might be 

 shown to flow. This element was to be at once the source 

 and the test of every conception of the human conscious- 

 ness. This he supposed he found in the " simple impres- 

 sion" or "simple impression of sensation." The essence 

 of Hume's method is to reduce all so-called knowledge of 

 objects to this test ; his constant demand is — show me 

 the "impression" from which your alleged conception or 

 idea is derived, and then, but then only, shall I admit the 

 reality and validity of your knowledge. If our conception 

 be meaningless, the object of it is unreal. It is easy to see 

 how on such a method, whether adopted hypothetically 

 or dogmatically, self-existence, self-identity, personality, 

 and Deity must be given up. 



But the question at once arises: — What precisely is 

 this so-called '■'■impression of sensation^'' or "singular 

 sensation ? " The psychological method has been ad- 

 mitted. And we must apply this method to find whether 

 there is such a thing as an impression per se. It is at 

 least a consciousness, or state of consciousness. If it be 

 said that impression is not the full fact, but a mere 

 abstract part of the complex fact which we call conscious- 

 ness — this is a position which is quite as vindi cable on 

 Hume's psychological method as his statement of the fact 

 is. We do not require to have recourse here to any 

 " transcendental deduction," or to Prof. Huxley's "pure 

 metaphysician." We only ask whether the psychological 

 method is fairly applied to the fact. Here we do not 

 think that Prof. Huxley has done any justice to those 

 who say and seek to show that impression per se is a 

 mere abstraction — possibly even a simple unintelligibility- 



No doubt Prof. Huxley tells us that Hume omitted an 

 entirely irresolvable element of consciousness, viz., rela- 

 tion, as of succession, co-existence, &c. But one does 

 not see that Prof. Huxley apprehends the true force of 

 his own admission. The relation of succession is still as 

 much an abstraction as impression is, in fact, an unintel- 

 ligibility, unless on the supposition of some one con- 

 scious being, — subsisting through varying times. An 

 appeal to memory is of no use here. Memory itself is but 

 a phrase for the act of one and the same conscious being 

 subsisting and recognising impressions in successive 

 times. The unity of the conscious being is the ground 

 of memory ; not memory the ground of it ; as this unity is 

 equally the ground of the possibility of a known relation 

 of succession, or successive impressions. Prof. Huxley 

 does not recognise this in its proper place ; he even in 

 the end gives in his adhesion to Hume's denial of a self 

 or unity in consciousness at all. But by this he cuts away 

 all ground of right to acknowledge relation in knowledge ; 

 all ground in fact to affirm or deny anything. 



Hume at once naturally takes iip the question as to the 

 kinds of impressions conveyed, as he phrases it, through 

 the senses. His answer to this question may be said to 

 be that all we know through the senses is of the same 

 kind, Avhatever be our natural belief to the contrary. 

 Figure, bulk, motion, colours, tastes, smells, sounds, heat 

 and cold — pains and pleasures, from application of objects 

 to our bodies — are all simply impressions or conscious 

 states— each class has but the same "interrupted and 



dependent being." They are *' nothing but perceptions 

 arising from the particular configurations, and motions of 

 the parts of bodies." In that sentence lies the main 

 inconsistency of Hume ; and it is a key to the constant 

 shifting of ground, which, with all deference to the ad- 

 mirers of the consistency and cogency of his reasoning, 

 nullifies large portions at once of the " Treatise of Human 

 Nature," and the "Inquiry Concerning Human Under- 

 standing." For if the senses can in no way give us more 

 than a conscious impression, they are absolutely impotent 

 to tell us of a body which is not itself merely a conscious 

 impression. And to say, therefore, that bodily motions are 

 the antecedents or causes of conscious impression is 

 simply to say that conscious impression is the antecedent 

 or cause of conscious impression. If Hume assumes that 

 the senses do more than this, and distinctly inform us of 

 objects called body and bodily motion, then he contradicts 

 his own doctrine regarding the reach and sphere of the 

 senses. And if he holds that body is the cause of impres- 

 sions, he must admit a clear knowledge both of body and 

 of what it can do. 



But Hume is represented as stating and refuting 

 with effect "the arguments commonly brought against 

 the possibility of a causal connection between the modes 

 of motion and the cerebral substance and states of 

 consciousness" (p. •](>). Hume's argument is as follows : 

 Cause is simply constant conjunction ; a priori, any- 

 thing may produce anything ; no reason is discoverable 

 why any object may or may not be the cause of any 

 other, however great or little the resemblance between 

 them. Thought may therefore be the effect of motion ; 

 we may perceive a constant conjunction of motion and 

 thought. Nay, it is certain we have this perceptipn, 

 " since the different dispositions of the body change the 

 thoughts and sentiments." Hence ** motion may be, 

 and actually is, the cause of thought and perception." 



In this so-called proof Hume evidently felt in a dim way 

 the force of the objection, that, on his doctrine, thought 

 and motion are really identical, that in fact he was only 

 surreptitiously begging for motion, a character which his 

 system denied it — the vulgar realistic view — in order to 

 prove that thought as a distinct thing from motion was 

 yet produced by it. Accordingly we find a clause, as is 

 Hume's manner, quietly inserted to blunt this criticism by 

 the way, "We find," he says incidentally, "by the com- 

 paring the ideas that thought and motion are different 

 from each other." Possibly enough that is so ; but the 

 difference, whatever it may be, cannot, on Hume' s doc- 

 trine at least, be allowed to extend beyond the common 

 genus of conscious impressions ; and it is, therefore, 

 wholly irrelevant to his argument. 



Prof Huxley must know that all psychologists of note, 

 and of the most different schools, from Hartley to Hamilton, 

 have admitted the fact of "constant conjunction," of 

 bodily organic impressions with conscious sensations and 

 perceptions. But after all that Prof. Huxley has said, as 

 to the place which this organic impression has in the pro- 

 duction of the sensation, the questions remain whether it is 

 the cause, or a concause, or merely a condition, on which 

 a higher power comes into play. Prof. Huxley has surely 

 read of the fact of mental absorption— that state of mind 

 in which, when it is occupied by strong emotion, or by in- 

 tense thought, all the organic impressions may take place, 



