438 THE POPULAR SCIENCE MONTHLY. 



displayed by Bishop Butler in rolling back a difficulty on his oppo- 

 nent ; and they even imagine that it is the bishop's own argument 

 that is there employed. Instructed by self-knowledge, they can hardly 

 credit me with the wish to state both sides of the question at issue, 

 and to show, by a logic stronger than Butler ever used, the overthrow 

 which awaits any doctrine of materialism which is based upon the 

 definitions of matter habitually received. But the raising of a new 

 difficulty does not abolish does not even lessen the old one, and the 

 argument of the Lucretian remains untouched by any thing the bishop 

 has said or can say. 



And here it may be permitted me to add a word to an important 

 controversy now going on. In an article on " Physics and Metaphysics," 

 published in the Saturday Review more than fourteen years ago, I ven- 

 tured to state thus the relation between physics and consciousness : 

 " The philosophy of the future will assuredly take more account than 

 that of the past of the relation of thought and feeling to physical pro- 

 cesses ; and it may be that the qualities of Mind will be studied 

 through the organism as we now study the character of Force through 

 the affections of ordinary matter. We believe that every thought and 

 every feeling has its definite mechanical correlative in the nervous sys- 

 tem that it is accompanied by a certain separation and remarshaling 

 of the atoms of the brain. 



" This latter process is purely physical ; and were the faculties we 

 now possess sufficiently strengthened, without the creation of any new 

 faculty, it would doubtless be within the range of our augmented 

 powers to infer from the molecular state of the brain the character of 

 the thought acting upon it, and, conversely, to infer from the thought 

 the exact corresponding molecular condition of the brain. We do not 

 say and this, as will be seen, is all-important that the inference here 

 referred to would be an a priori one. What we say is, that by observing, 

 with the faculties we assume, the state of the brain, and the associated 

 mental affections, both might be so tabulated side by side, that if one 

 were given, a mere reference to the table would declare the other. 



" Given the masses of the planets and their distances asunder, and 

 we can infer the perturbations consequent on their mutual attractions. 

 Given the nature of a disturbance in water, air, or ether, and from the 

 physical properties of the medium we can infer how its particles will 

 be affected. The mind runs along the line of thought which connects 

 the phenomena, and, from beginning to end, finds no break in the chain. 

 But, when we endeavor to pass by a similar process from the phenom- 

 ena of physics to those of thought, we meet a problem which transcends 

 any conceivable expansion of the powers we now possess. We may 

 think over the subject again and again it eludes all intellectual 

 presentation we stand, at length, face to face with the Incompre- 

 hensible." 



The discussion above referred to turns on the question : Do states 



