CH. III.] ACTIONS OF INSTINCTS. 135 



again, descends to the sea, and is drowned. Lastly, experience 

 teaches us, that when men attempt to develop the instincts in 

 themselves or other animals voluntarily, or to regulate, limit, 

 or extend them, they usually fail, and miss the object of nature, 

 which would more rarely happen, if the instincts were blindly 

 allowed to act, without the interference of their own notions. 



267. Nevertheless, it is also certain, that the operations of 

 the blind instincts do not appear to harmonise in all cases with 

 the objects of nature : this may arise possibly from the fact, that 

 we do not sufficiently comprehend those objects ; or else that the 

 instincts are rendered incapable of their attainment, where their 

 actions are influenced volitionally by the intermingling of the 

 actions of other sentient forces. It is observed, for example, 

 that many animals are not sufficiently taught by their instinct, 

 not to eat or do certain things which are injurious to them. 

 Some eat poisonous herbs without suspicion, and are poisoned. 

 Many exceed their strength so much in the accomplishment of 

 their instincts, that they become quite enfeebled and die. In 

 cases of this kind we are ignorant what are the designs of nature 

 in the implantation of instincts, or what is the object in limiting 

 the sphere of their utility to the personal weal of the animal, 

 and not extending it to all possible cases. To what extent we 

 ourselves hinder the designs of nature in the instincts, and limit 

 their operations by the interference of our will, is shown by 

 their great uncertainty in mankind, and their much greater cer- 

 tainty in those animals which follow them blindly ; but especially 

 is it shown in disease, when we attribute that to an instinct of 

 nature, which is only the consequence of intellectual desires. 



268. It is requisite to the attainment of the objects of the 

 instincts, that the inducements previously appointed by nature, 

 shall excite the pleasure or suffering, which will develop a cer- 

 tain foreseen future agreeable or unpleasant sensation (94, 262). 

 These sensational stimuli excite that effort which is the instinct 

 itself (80,83), and the satisfaction of which nature afterwards pro- 

 vides by means prepared beforehand (262) . In this development, 

 the natural inducements of the instinct are to be most carefully 

 distinguished from its sensational stimuli, — the latter from the 

 instinct itself, — and the instinct from its contentment or satis- 

 faction. It is thus that we find the whole order of the pheno- 

 mena of instinct to occur in nature. With the object of causing 



