CH. II.] MATERIAL IDEAS. 27 



material idea in the brain (25). Consequently, the material 

 ideas of more vigorous conceptions are more compound and more 

 vigorous movements than those of the weaker ; and for similar 

 reasons, the conceptions of more vigorous material ideas are more 

 compound and larger conceptions than those of the weaker. 



27. All conceptions are operations of the sentient force, and 

 consequently acts of the soul. All material ideas are operations 

 of the animal-sentient force of the brain (25, 26), consequently 

 they are operations of the animal motor forces of an animal 

 machine. But since neither can exist without the other, the 

 conceptions, as well as the material ideas in general, are effected 

 by means of the two co-operating forces of the soul and brain. 

 When the animal machines produce material ideas in virtue 

 of antecedent impressions derived from without, and thus induce 

 the co-operation of the conceptive force, — such as takes place, 

 for example, in external sensations, — conceptions thus origi- 

 nated are termed purely natural)- (impressional) conceptions^ 

 which arise in the mind, necessarily and physically (Baum- 

 garten^s ^Metaphysics,' § 522), and succeed each other according 

 to the laws of external impressions, so far as they put the 

 animal- sentient force of the brain into activity. When, on 

 the other hand, conceptions, and their material ideas, are de- 

 veloped by the sentient force, independently of any previous 

 external impressions in the animal machines, and thus induce 

 the co-operation of the animal-sentient force of the brain, as, 

 for example, in volitional acts, — these conceptions are termed 

 arhitrary , spontaneous, physiologically free^ (Baumgartner, §520 ; 

 Hallers's 'Physiology,' § 570); and they succeed each other ac- 

 cording to the laws of the sentient force. Neither the purely 

 impressional, nor the spontaneous conceptions, can have a real 

 existence, independently of material ideas (25), and when they 

 continue, must embody their impressions in the brain (26). But 



* The term naturlich, here translated natural, has a pecuUar meaning, being used 

 generally in the sense of organic, somatic, or corporeal, or to express something antago- 

 nistic to spiritual. I have ordinarily translated it by natural, organic, or physical. 



* The reader is particularly requested to observe, that the words " arbitrary" and 

 '* spontaneous" are used here and elsewhere throughout the work in their strict 

 etymological and metaphysical sense, and indicate conceptions or actions caused or 

 excited by the will, as a faculty of mind. This remark is necessary, because, popu- 

 larly, the word " arbitrary," indicates acts that are despotic, absolute, or capricious ; 

 while " spontaneous" is applied to acts done without compulsion. The words in 

 the original are eigenmdchtig and selhstthdtig. — Ed. 



