vi] Sylvius and his Pupils. 171 



"other hand is twin to the essential, absolute and genuine 

 " nature of the soul itself, — a something which is in itself 

 " incorporeal, just like the soul itself, but powerful and active 

 "in the actual body, like again the soul itself. Moreover, 

 " it is clear that this something ministers to the wants of 

 11 the soul, not only so far as the existence and maintenance of 

 "the body is concerned, but also and especially in the naked, 

 " pure, and direct uses and purposes of the soul. And that in 

 "such a way that the soul even in its highest functions and 

 "in its supreme activity has such clear, true, full power over 

 " this something of which we are speaking, that it quite 

 " absolutely governs it, increases it, diminishes it, and turns 

 " or directs it, according to its judgment. This something 

 "indeed so simply and absolutely belongs to the soul, even 

 " in its most direct acts, that whenever anything which is 

 " truly and essentially belonging to a part of the soul sets out 

 "to become active, or to accomplish anything, it always 

 " discharges that duty, always accomplishes that act by means 

 " of this very something of which I am speaking, which thus 

 " serves as its true instrument ; this something, however, is 

 "nothing else than 'motion.' By motion indeed the soul 

 "carries out all its doings." 



And he goes on to shew how all the phenomena of the 

 living body, in their threefold aspects, the phenomena con- 

 cerned in the preservation of the material composition of the 

 body, in the formation and repair of structures, and in sensation 

 with all its consequences, are all of them, to use the words of a 

 modern writer, at bottom ' modes of motion.' 



Stahl applies these views to the physiology of digestion. 

 He admits, or seems to admit, fermentation as a property of 

 non-living things, and seems to regard putrefaction as a sort 

 of fermentation also possible in and belonging to non-living 

 things. He even seems to admit that the ferments of saliva 

 and pancreatic juice are such non-living agencies ; though he 

 refuses to believe in a gastric ferment. " Some people suppose 

 " that gastric digestion results from the action of particular 

 " and specific ferments, and indeed go so far as to regard the 

 " stomach as not only the seat but also the origin of a particular 



