574 THE SENSORIAL FUNCTIONS. 



pulse, to the performance of the actions required 

 for those ends. We see animals providing 

 against the approach of winter, the effects of 

 which they have never experienced, and em- 

 ploying various means of defence against ene- 

 mies they have never seen. The parent consults 

 the welfare of the offspring she is destined never 

 to behold ; and the young discovers and pursues 

 without a guide that species of food which is 

 best adapted to its nature. All these unex- 

 plained, and perhaps inexplicable facts, we must 

 content ourselves with classing under the head 

 of instinct; a name which is, in fact, but the 

 expression of our ignorance of the nature of that 

 agency, of which we cannot but admire the 

 ultimate effects, while we search in vain for the 

 efficient cause. 



In all the inferior orders of the animal crea- 

 tion where instincts are multiplied, while the 

 indications of intellect are feeble, the organ 

 which performs the office of the brain is compa- 

 ratively small. The sensitive existence of these 

 animals appears to be circumscribed within the 

 perceptions of the moment, and their voluntary 

 actions have reference chiefly to objects which 

 are present to the sense. In proportion as the 

 intellectual faculties of animals are multiplied, 

 and embrace a wider sphere, additional magni- 

 tude and complication of structure are given to 

 the nervous substance which is the organ of 



