62 EVOLUTION AND MAN S PLACE IN NATURE 



none of the animals have we attributed high rational 

 ising powers. 



In marking here the limits of physiological dis 

 covery, it will be observed that we are seeking only 

 localisation of functions ; we are not dealing with the 

 natural history of their appearance. At this stage, I 

 do no more than remark as a notable fact that science 

 has not localised reflective procedure. On questions 

 of comparative intelligence, involving differences be 

 tween animal life and human, I do not enter now. 

 These will come in due course. From study of our 

 own rational power, we shall be better able hereafter 

 to contemplate animal intelligence. Our single con 

 clusion here is, that conspicuous phases of ordinary 

 human activity have not been proved to lie within 

 range of physiology. The phenomena of sensibility 

 and of motor activity have been localised in the brain ; 

 the phenomena of rational life have not been so 

 localised. Science thus leaves the way open for 

 our inquiry, whether rational phenomena altogether 

 transcend the functions of organism. The need for 

 dealing with this problem is not affected by the 

 admission that brain is the organ of mind. This 

 position gives force to the rational demand here 

 indicated. Looking at the natural history of human 

 life, Darwin has said : As the various mental faculties 

 gradually developed themselves, the brain would 

 almost certainly jDecome larger. 1 This seems to me 

 perfectly certain, under the law that use favours 

 development. v But the statement presupposes mind 

 in active exercise, and brain as an organ directedln 

 functional activity by a power superior to itself. The 

 1 Descent of Man, p. 54. 



