in FUNCTION OF MIND AND BRAIN 35 



ence, perhaps of a whole mass of experiences, in which similar 

 perceptions have in our previous history been concerned. 



(4) But it is not only our own history which forms our 

 mental structure. The experience on which a suggestion 

 rests may be irrecoverable by memory, for the simple reason 

 that it never occurred within the range of memory. The 

 mind, as part of the whole psycho-physical structure, grows 

 up under the influence of heredity as a whole, and in its 

 several parts it arises, survives and is modified from genera- 

 tion to generation in accordance with vital needs. The 

 main need which the mind functions subserve is that of 

 directing response to the environment, and the direction 

 must in the main be that which tends to the preservation of 

 race. Under these influences arises a mind- structure en- 

 dowed with definite tendencies of reaction, quick, for 

 instance, to respond with perception to certain external 

 movements which threaten the safety of the organism, and 

 not only with perception, but with appropriate motion and 

 appropriate feeling. Here again we must in any individual 

 case be on our guard against the old fallacy. When we see 

 a fish dart away in response to a sudden movement of our 

 own we must not hastily impute to the fish a series of dis- 

 tinct operations such as the perception of a moving 

 object, a fear of attack, and resolution to fly. For all we 

 know the fish may be capable neither of perception, emotion 

 or resolve. What we see is the responsive motion, which 

 would be logically justified by the fear of danger, which 

 fear again might be logically justified by an experience of 

 men and of their unkind dealings with fish. If the fish is 

 capable of mental processes, and if these mental processes 

 correspond, as they may, to certain of the lower processes 

 of our own mind, we may put it that what actually passes in 

 the supposed case is a process which contains all the elements 

 enumerated in germ, but none of them in maturity or 

 distinctness. 



For among ourselves the primal basis of our reactions is 

 not reflective. It is not even due to experience. It is a 

 part of that original equipment which we call hereditary, 1 



*We know not where to look for the source of any element in our 

 original equipment except in the physical antecedents of our birth. So 



