CH. III.] ACTIONS OF INSTINCTS. 139 



or of solitude, accompany the instinct of .love, whilst in man, 

 the understanding and will often co-operate with the instincts. 

 It follows from hence that many movements occur conjointly 

 with the actions of the instincts, particularly in those animals, 

 which are capable of conceptions only remotely connected with 

 external sensations (27) ; and thus a highly compound and 

 complicated condition of the mind and the body may arise, 

 which can never be explained by the nature of the instincts, as 

 has been often uselessly attempted, so long as the subordinate 

 conceptions, together with their accompanying actions, are not 

 carefully distinguished from the instinct itself and its acts. If 

 the acts, for example, resulting from the satisfaction of the 

 instinct, be confounded with those of the instinct itself, the 

 greatest mistake is made. And one great reason why the 

 nature and operations of the instincts and passions have been 

 hitherto so imperfectly elucidated is, that they have been cha- 

 racterised confusedly. It will, therefore, be worth while to 

 take an instinct as an example for analysis ; and for this pur- 

 pose I select the instinct of propagation, as the most important 

 and the most complicated. 



274. In this instinct, nature in the first instance impart 

 certain inducements to the animal, — external impressions 

 which surprise it (in Staunen setzen), and by means of a pe- 

 culiar action in the sexual organs, prepare the latter for the 

 sensational stimulus of the instinct, so that their nerves become 

 more sensitive to touch, so as to receive the gentle titillation 

 which constitutes the incitement of the instinct. This peculiar 

 impression causes in the minds of animals during heat only, 

 and at no other time, certain external sensations, and other sen- 

 sational conceptions, in accordance with the prearrangement of 

 nature (265). For example, the odour of an animal of the oppo- 

 site sex, a sound, a song, a whining, a chirp, a look, or a sensa- 

 tional conception, imagination, or foreseeing of them by an animal 

 in a state of heat, &c., develops the sentient actions in the me- 

 chanical machines (sexual organs) assigned to them by nature ; 

 for example, an increased flow of fluids to those organs, and 

 the increased secretion of the seminal fluid, and its accumula- 

 tion in the vesciculse seminales, in consequence of which they 

 become gently distende d and excited ; and thus the agreeable 

 external sensation in the sexual organs (the gentle titillation). 



3arts^>^jv 



