154 ESSAYS OF A BIOLOGIST 



it, and so laying the best possible foundations for 

 future repression. Or, on the other hand, they may 

 openly adopt the psycho-analytic view as to the role 

 of sex in the development of mind, may further be- 

 lieve that the fullest analysis and self-knowledge is 

 always desirable, and may accordingly be pointing 

 out to the child interpretations of its actions and 

 sayings in terms of sex, familiarizing it with sex from 

 the outset, not merely not discouraging but actually 

 encouraging reference to sexual matters. This will 

 tend, ceteris paribus, to the development of a mind 

 in which many of the more complex mental opera- 

 tions will not usually persist because the subject will 

 be continually unbuilding them into their constit- 

 uent parts, of which sex will be the most unvarying 

 and important. 



Both these types are to my judgment obviously 

 unsatisfactory. The ideal organization of the mind 

 must be one in which first there is a minimum of 

 waste of energy, secondly a maximum realization of 

 potentiality. The operations of mind may further 

 be thought of from two different angles — a subserv- 

 ing the biological needs of the organism, or as ends 

 in themselves. From the first point of view, thought 

 is action in posse: efficiency and full utilization of 

 energy are here the requirements, and it is obvious 

 that any method which even partially separates one 

 part of the mental organization from the rest must 

 be a poor one, that a refusal to face any portion of 

 reality, such as, in our special case, the physical side 



