70 THE FOUNDATIONS OF ZOOLOGY 



need be no necessary antagonism between those who attribute the 

 development of the germ to mechanical conditions and those who 

 attribute it to the inherent potency of the germ itself. 



We must now ask whether there is any more necessary antag- 

 onism between those who attribute knowledge to experience and 

 those who attribute it to our innate reason. 



If this question could be considered in itself, it might not be 

 formidable ; but it is hedged about with complications, for some of 

 which the modern zo5logist is responsible, although only a few of 

 the perplexities by which his efforts are beset can be laid to his 

 own charge. 



Some zoologists tell us that the value of our responses is equiva- 

 lent to confidence in their value, although it is clear that our hearts 

 had value before men studied anatomy, and that digestion was 

 useful to them before they knew that it occurs. 



We are also told, in effect, that confidence in the value of our 

 mental states is the same as judicious confidence in their value, 

 although we all know that while one who has led an uneventful 

 life may dread all accidents, a life of adventure may teach that, 

 while some accidents are to be avoided at any cost, the danger from 

 others is trifling. The confidence of the man with little experience 

 is no less strong than that of the adventurer, but it is less judicious ; 

 and, as we use words, we do not call it knowledge, but " ignorant " 

 prejudice, or "unreasoning" cowardice, although there is no reason 

 why those who wish should not use words in some other sense. 



The question whether experience is or is not the only source of 

 knowledge clearly turns, in part at least, on our definition of know- 

 ledge. An infant who has never known a tumble may act as they 

 act who know the danger of a fall, and, if response to the order of 

 nature were evidence of knowledge, it would be obvious that some 

 knowledge is innate, or independent of experience ; but it is not our 

 custom to call the blind prejudice of ignorance and the prudent 

 conservatism of the wise by the same name. 



Some zoologists hold that beneficial response to a stimulus is 

 evidence that the stimulus is perceived, and that the response is 

 made with knowledge, and, if this were admitted, it would be clear 

 that some knowledge is innate in living things ; for all admit 

 that they may respond to the order of nature without experience, 



