PROFESSOR TYNDALUS ADDRESS. 66^ 



glasses, the like may justly be conelucled from analogy of all our 

 senses." 



Lucretius, as you are aware, reached a precisely opposite conclu- 

 sion ; and it certainly would be interesting, if not profitable, to us all, 

 to hear what he would or could urge in opposition -to the reasoning 

 of the bishop. As a brief discussion of the point will enable us to 

 see the bearings of an important question, I will here permit a disci- 

 ple of Lucretius to try the strength of the bishop's position, and then 

 allow the bishop to retaliate, with the view of roiling back, if he can, 

 the difficulty upon Lucretius. Each shall state his case fully and 

 frankly, and you shall be umpire between them. The argument 

 might proceed in this fashion : 



" Subjected to the test of mental presentation ( Vorstellu7ig) your 

 views, most honored prelate, would present to many minds a great, if 

 not an insuperable difficulty. You speak of ' living powers,' * percipi- 

 ent or perceiving powers,' and ' ourselves ; ' but can you form a men- 

 tal picture of any one of these apart from the organism through which 

 it is supposed to act ? Test yourself honestly, and see whether you 

 possess any faculty that would enable you to form such a conception. 

 The true self has a local habitation in each of us ; thus localized, must 

 it not possess a form ? If so, what form ? Have you ever for a mo- 

 ment realized it ? When a leg is amputated, the body is divided into 

 two parts ; is the true self in both of them or in one ? Thomas Aqui- 

 nas might say in both ; but not you, for you appeal to the conscious- 

 ness associated with one of the two parts to prove that the other is 

 foreign matter. Is consciousness, then, a necessary element of the 

 true self? If so, what do you say to the case of the whole body be- 

 ing deprived of consciousness ? If not, then on what grounds do you 

 deny any portion of the true self to the severed limb ? It seems very 

 singular that, from the beginning to the end of your admirable book 

 (and no one admires its sober strength more than I do), you never 

 once mention the brain or nervous system. You begin at one end of 

 the body, and show that its parts may be removed without prejudice 

 to the perceiving power. What if you begin at the other end, and re- 

 move, instead of the leg, the brain ? The body, as before, is divided 

 into two parts ; but both are now in the same predicament, and nei- 

 ther can be appealed to to prove that the other is foreign matter. 

 Or, instead of going so far as to remove the brain itself, let a certain 

 portion of its bony covering be removed, and let a rhythmic series of 

 pressure and relaxations of pressure be applied to the soft substance. 

 At every pressure ' the faculties of perception and of action ' vanish ; 

 at every relaxation of pressure they are restored. Where, during the 

 intervals of pressure, is the perceiving power ? I once had the dis- 

 charge of a Leyden battery passed unexpectedly through me : I felt 

 nothing, but was simply blotted out of conscious existence for a sen- 

 sible interval. Where was my true self during that interval ? Men 



