28 THE POPULAR SCIENCE MONTHLY, 



they would still remain perfectly unintelligible. Astronomical knowl- 

 edge of the brain — the highest grade of knowledge we can expect ever 

 to have — discloses to us nothing but matter in motion. But we can- 

 not, by means of any imaginable movement of material particles, 

 bridge over the chasm between the conscious and the unconscious. 



Motion can only produce motion, or be converted back into j^oten- 

 tial energy. Potential energy can only produce motion, maintain static 

 equilibrium, or exert pressure or traction. The sum of energy, how- 

 ever, remains the same. Beyond this law nothing can go in the phys- 

 ical world, nor can any thing fall short of it; the mechanical cause 

 passes completely into the mechanical effect. Hence the mental phe- 

 nomena, which in the brain appear in company with material phenom- 

 ena, are, so far as our understanding is concerned, void of sufficient 

 basis. They lie beyond the law of causality, and hence are unintel- 

 ligible, like a mobile perpetuum. But they are also unintelligible on 

 other grounds. 



True, on superficial observation, it looks as though certain mental 

 operations and conditions might be intelligible to us, from a knowl- 

 edge of the material phenomena of the brain. Among such mental 

 phenomena I might reckon memory, association of ideas, habit, specific 

 talents, etc. It needs but little reflection to show that this is an error. 

 We should only be acquainted with certain inner conditions of the 

 soul's life, which are of about equal import with the external con- 

 ditions created by sense-impressions ; but we should know nothing 

 about the origin of mental life in virtue of these conditions. 



What conceivable connection subsists between definite movements 

 of definite atoms in my brain, on the one hand, and on the other hand 

 such (for me) primordial, indefinable, undeniable facts as these: "I 

 feel pain, or pleasure ; I experience a sweet taste, or smell a rose, or 

 hear an organ, or see something red," and the immediately-consequent 

 certainty, " Therefore I exist ? " It is absolutely and forever incon- 

 ceivable that a number of carbon, hydrogen, nitrogen, oxygen, etc., 

 atoms should not be indifferent as to their own position and motion, 

 past, present, or future. It is utterly inconceivable how consciousness 

 should result from their joint action. If their respective positions and 

 their motion were not indifferent to them, they would have to be re- 

 garded as each possessed of a consciousness of its own, and as so many 

 monads. But this would not explain consciousness in general, nor 

 would it in the least assist us in understanding the unitary conscious- 

 ness of the individual. 



That it is and ever will remain utterly impossible to understand 

 higher mental operations from the mechanics of the cerebral atoms 

 (supposing them to be known), needs not to be proved. Yet, as has 

 been already remarked, we need not consider the higher forms of men- 

 tal activity, in order to add weight to our argument. But its force is 

 intensified by contrasting the absolute ignorance wherein astronomical 



