324 LECTURE XIV. 



violent opposition is still made to the introduction of the 

 same principle also into the animal economy, there is, I 

 think, no other difficulty in the way but the one, that ses- 

 thetical and moral scruples cannot be overcome. 



It cannot of course here be our business either to 

 refute these scruples or to point out how they might be 

 reconciled with the views I advocate. I have only to 

 show in how great a degree the pathological processes 

 which especially interest us, in all cases conduct us back 

 to the same cellular principle, and how much they are 

 in every case opposed to that notion of a single con- 

 trolling principle, which is sought to be established by 

 the neuro-pathologists. This opinion of mine has after 

 all really nothing new or uncommon in it. If for thou- 

 sands of years the life of the individual parts of the 

 body has been talked about, if the position is admitted, 

 that in diseased conditions the death of individual parts, 

 necrosis or gangrene in them may take place, whilst the 

 whole still continues to exist the inference is, that 

 something of our way of thinking had long been ex- 

 pressed in the views held by the world in general : only 

 people had not formed very clear notions upon the subject. 

 If we speak of the life of the individual parts of a 

 body, we must also know in what way life manifests 

 itself, and whereby it is essentially characterized. This 

 characteristic we find in activity, an activity indeed, in 

 which there is displayed by every single part, whilst it 

 contributes its contingent, according to its peculiarities, 

 to the general activity of the body something identical 

 with the life of the other parts ; for else we should be in 

 no way justified in regarding life as something in every 

 case similar, and derivable from some common origin. 



This vital activity is, as far at least as we are able to 

 judge, nowhere, in no part whatever, carried on by 

 means of any cause allotted to it from the very begin- 



