INTRODUCTION. 15 



forces or nerve forces [vis nervosa], and their movements are 

 purely animal or nerve-actions} 



Note. — It is absolutely necessary, that these various animal 

 forces and their modes of action should each have their distin- 

 guishing designations, and I have not been able to invent more 

 convenient terms than the preceding. They might have been 

 termed simply mental forces and nerve forces ; but since the 

 former term is already applied to designate the powers of the 

 mind, the affix animal must be used to distinguish the mental 

 forces of the sentient animal body. 



7. By virtue of their animal nature, the bodies of animals 

 acquire forces, which cannot be explained by the physical and 

 mechanical laws applicable to the motion of other bodies and 

 machines, and which can act only through the proper animal 

 machines. Their workings are manifested partly in the latter, 

 partly in the other machines of the bodies, upon the forces and 

 movements of which they stamp the animal characteristics. 

 With these (primary) animal forces the influence of the soul 

 on the body, and also the moving forces peculiar to the animal 

 machines, are to be classed. 



' The term Thierischer kbrper, as used by Unzer, exactly corresponds to the 

 modern phrase, animal organism. The word kr'dfte might he rendered forces, 

 powers, properties, faculties, or vis. In (3), kraft is applied to express the force of 

 attraction and repulsion ; and I have, therefore, used that word as its synonym, 

 although it is evident that Unzer uses the word rather indefinitely ; and the 

 Thierische krdfte, mentioned in the text, might more fitly be designated powers or 

 properties than forces. The true synonym is vis nervosa (639). Thierische-seelen- 

 krafte is a compound word, for which it is impossible to find an English synonym ; 

 it is used to signify the properties or functions of the brain, so far as that organ is 

 the seat of consciousness, or, more abstractedly, the combination in action of the 

 purely animal force {vis nervosa) with the mental. In either case the term implies 

 the action of mind and the existence of consciousness or will. When used in the 

 former sense, I have rendered the phrase by cerebral forces ; when in the latter, by 

 animal- sentient forces. Whenever the word seele is used in the original, either 

 adjectively or in compound words, to express circumstances dependent on the exist- 

 ence of soul or mind, as in beseelte, &c. (349, 603), I have rendered it by sentient. 

 Vorstellung is used indefinitely in the sense of sensation, perception, conception, 

 thought, or of an act of mind generally (vide 25, 34-36) ; and Vorstellungskraft to 

 signify the power or force by which we feel, perceive, think, or will. I have trans- 

 lated Vorstellung generally by the term conception, and consequently use the word 

 conceptive force as the best rendering of Vorstellungskraft ; but where the context 

 required or allowed, I have also rendered it by sentient force, or, more simply, by 

 mmrf.— Vide note to $ 25.— Ed. 



