TABLE OF CONTENTS xiii 



CHAP. PAGE 



V. Of the Force which produces the Actions of Ani- 

 mals, AND OF certain PECULIAR FACTS RESULTING 

 FROM THE USE OF THIS FORCE - - . - 343 



That since muscular action is a power fully adequate for the 

 production of the movements performed by animals, and since 

 nervous influence is able to excite that muscular action, such 

 animals as have physical feeling possess in their inner feeling a 

 power quite capable of driving to the muscles the fluid which 

 excites their movements ; and it is in fact by its emotions that 

 this feeling obtains the force to work the muscles. 



Of THE Consumption and Drainage of the Nervous 



Fluid in the Production of Animal Actions - 348 



Of the Origin of the Propensity towards repeating 



THE Same Actions --.-.. 349 



Of Instinct in Animals - 350 



Of Skill in Certain Animals 353 



VI. Of the Will -------- 355 



That, since the will always results from a judgment, and since 

 a judgment necessarily arises from a comparison of ideas, a 

 thought, or some impression that causes it, every act of will is 

 an act of intelligence, and that consequently only animals with 

 a special organ for intelligence can carry out acts of will. 



That, since the will always depends on a judgment, not only 

 is it never really free, but, since judgments are liable to numerous 

 causes of error, the will resulting from them is less reliable than 

 instinct in the inner feeling driven by some need. 



VII. Of the Understanding, its Origin, and the Origin 



of Ideas - - 362 



That all acts of the understanding require a special system of 

 organs for their execution ; that acquired ideas are the material 

 of all operations of the understanding ; that although every idea 

 is originally a sensation, every sensation need not become an 

 idea, since a special organ is necessary for its formation, and the 

 sensation, moreover, has to be noticed ; finally, that, in all acts of 

 intelligence, the nervous fluid is the only active factor, in that it 

 moves in the organ concerned, while the organ itself remains 

 passive, simply providing for the diversity of the operations by 

 the diversity of its parts. 



