638 FRAGMENTS OF 



thought, I acknowledge my helplessness. The association 

 of both with the matter of the brain may be as certain as 

 the association of light with the rising of the sun. But 

 whereas in the latter case we have unbroken mechanical 

 connection between the sun and our organs, in the former 

 case logical continuity disappears. Between molecular 

 mechanics and consciousness is interposed a fissure over 

 which the bidder of physical reasoning is incompetent to 

 carry us. We must, therefore, accept the observed associ- 

 ation as an empirical fact, without being able to bring it 

 under the yoke of a priori deduction. 



Such were the ponderings which ran habitually through 

 my mind in the days of my scientific youth. They 

 illustrate two things a determination to push physical 

 considerations to their utmost legitimate limit; and an 

 acknowledgment that physical considerations do not lead 

 to the final explanation of all that we feel and know. 

 This acknowledgment, be it said in passing, was by no means 

 made with the view of providing room for the play of con- 

 siderations other than physical. The same intellectual 

 duality, if I may use the phrase, manifests itself in the 

 following extract from an article entitled " Physics and 

 Metaphysics," published in the Saturday Review for 

 August 4, 1860: 



" The philosophy of the future will assuredly take more 

 account than that of the past of the dependence of thought 

 and feeling on physical processes; and it may be that the 

 qualities of the mind will be studied through organic com- 

 binations as we now study the character of a force through 

 the affections of ordinary matter. We believe that every 

 thought and every feeling has its definite mechanical 

 correlative that it is accompanied by a certain breaking 

 up and rernarshaling of tne atoms of the brain. This 

 latter process is purely physical; and were the faculties we 

 now possess sufficiently expanded, 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 on it, and, 

 conversely, to infer from the thought the exact 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. But by observing, with the 



