MAN AS THE INTERPRETER OF NATURE. 691 



too, the deliverances of our common-sense derive their trustworthiness 

 from what we consider the " self-evidence " of the propositions affirmed. 

 This inquiry brings us face to face with one of the great philosophical 

 problems of our day, which has been discussed by logicians and meta- 

 physicians of the very highest ability as leaders of opposing schools, 

 with the one result of showing how much can be said on each side. 



By the intuitionalists it is asserted that the tendency to form these 

 primary beliefs is inborn in man, an original part of his mental organi- 

 zation ; so that they grow up spontaneously in his mind as its faculties 

 are gradually unfolded and developed, requiring no other experience 

 for their geneses than that which suffices to call these faculties into 

 exercise. But, by the advocates of the doctrine which regards expe- 

 rience as the basis of all our knowledge, it is maintained that the pri- 

 mary beliefs of each individual are nothing else than generalizations 

 which he forms of such experiences as he has either himself acquired 

 or has consciously learned from others, and they deny that there is any 

 original or intuitive tendency to the formation of such beliefs, beyond 

 that which consists in the power of retaining and generalizing experi- 

 ences. 



I have not introduced this subject with any idea of placing before 

 you even a summary of the ingenious arguments by which these op- 

 posing doctrines have been respectively supported ; nor should I have 

 touched on the question at all, if I did not believe that a means of 

 reconcilement between them can be found in the idea that the intellect- 

 ual intuitions of any one generation are the embodied experiences of 

 the previous race. For, as it appears to me, there has been a progres- 

 sive improvement in the thinking power of man ; every product of the 

 culture which has preceded serving to prepare the soil for yet more 

 abundant harvests in the future. 



Now, as there can be no doubt of the hereditary transmission in 

 man of acquired constitutional peculiarities, which manifest them- 

 selves alike in tendencies to bodily and to mental disease, so it seems 

 equally certain that acquired mental habitudes often impress them- 

 selves on his organization, with sufficient force and permanence to 

 occasion their transmission to the offspring as tendencies to similar 

 modes of thought. And thus, while all admit that knowledge cannot 

 thus descend from one generation to another, an increased aptitude for 

 the acquirement, either of knowledge generally or of some particular 

 kind of it, may be thus inherited. These tendencies and aptitudes will 

 acquire additional strength, expansion, and permanence, in each new 

 generation, from their habitual exercise upon the materials supplied 

 by a continually-enlarged experience ; and thus the acquired habi- 

 tudes produced by the intellectual culture of ages will become " a sec- 

 ond nature " to every one who inherits them. 1 



1 I am glad to be able to append the following extract from a letter which Mr. John 

 Mill, the great Master of the Experimental School, was good enough to write to me a few 



