36 DEVELOPMENT AND PURPOSE CHAP. 



or in more familiar phrase it is instinctive. This hereditary 

 element is not to be confined to certain specific elements in 

 our mental life, to certain < forms of thought, 5 certain prin- 

 ciples of will, certain types of emotion. No doubt there 

 are points at which its influence is more distinct, less over- 

 laid by the effects of social tradition and personal experi- 

 ence. But rightly understood it permeates the entire life 

 of mind. In a sense its operation is most decisive in the 

 very department which is singled out as the especial pre- 

 serve of personal experience, the department of * pure 5 

 sensation. So far as a sensation is ' pure/ that is to say is 

 unmodified by elements of thought or by the unconscious 

 operation of previous experience, it represents the naked 

 reaction of the hereditary structure of mind on the given 

 stimulus. The poppies are red and the oak leaves green 

 to us because our organism is so constructed as to react to 

 the physical stimulus of vibrations of different wave- 

 lengths with those two sensations. That the one object is 

 a red poppy and the other an oak leaf are judgments in 

 which something more than pure sensation is involved. 

 That they are red objects is a judgment in which some- 

 thing more is involved. That the names red and green 

 apply to them are judgments in which something more 

 is involved. But in the quality of the sensation 'red,' 

 'green, 5 we come as near as we ever can to pure sensa- 

 tion, and therewith we come to that which depends on 

 the original hereditary endowment of the mind-structure. 

 This element will be found accordingly to pervade our 

 judgments of external things. It is even more obviously 

 present in our feelings and our impulses. It is operative 

 in our judgments and inferences. It is the original founda- 

 tion of our temperament and character. But all along, 

 until we reach the highest stages of reflection, it is in its 

 operation unconscious. That is to say it determines our 



we call the whole of it hereditary. But (a) there may be other sources 

 of which at present we know nothing, and (<) the use of the term 

 ' hereditary' does not imply any specific measure of likeness to our 

 parents. From generation to generation there is variation as well as 

 resemblance, and exactly how much there may be of either is a question 

 for the science of genetics to determine. 



