September 29, 1922] 



SCIENCE 



353 



■brain is the main seat of mind. That eoz'tes 

 with its twin halves corresponding to the two 

 side-halves of the body is really a single organ 

 knitting those halves together by a still further 

 knitting together of the nervous system itself. 

 The animal's great integrating system is there 

 still further integrated and this supreme inte- 

 grator is the seat of all that is most clearly 

 inferable as the animal's mind. As such it has 

 spelt biological success to its possessors. From 

 small beginnings it has become steadily a larger 

 and larger feature of the nervous system, until 

 in adult man the whole remaining portion of 

 the system is relatively dwarfed by it. It is not 

 without significance, perhaps, that in man this 

 organ, the brain cortex, bifid as it is, shows 

 unmistakable asymmetry. Man is a tool-using 

 animal, and tools demand asymmetrical, though 

 attentive and therefore unified, acts. A ner- 

 vous focus unifying such motor function will, 

 in regard to a laterally bipartite organ, tend 

 more to one half or the other and in man's 

 cerebrum the preponderance of one half, 

 namely, the left, over the other may be a sign 

 of unifying function. 



It is to the psychologist that we must turn 

 (to leam in full the contribution made to the 

 integration of the animal individual by mind. 

 But each of us can recognize, without being a 

 professed psychologist, one achievement in 

 that direction which mental endowment has 

 produced. Made tip of myriads of microscopic 

 eeU-lives, individually born, feeding and breath- 

 ing individually within the body, each one of 

 us nevertheless appears to himself a single 

 entity, a unity experiencing and acting as one 

 individual. In a way the more far-reaching 

 and many-sided the reactions of which a mind 

 i^ capable the more need, as well as the more 

 scope, for their consolidation to one. True, 

 each one of us is in some sense not one self, 

 but a multiple system of selv^. Yet how 

 closely those selves are united and integrated 

 to one personality. Even in those extremes of 

 so-called double personality one of their mysti- 

 fying features is that the individual seems to 

 himself at any one time wholly either this 

 personality or that, never the two commingled. 

 The view that regards hysteria as a mental 

 dissociation illustrates the integrative trend of 



the total healthy mind. Circumstances can 

 stress in the individual some, perhaps lower, 

 instinctive tendency that conflicts with what 

 may be termed his normal personality. This 

 latter, to master the conflicting trend, can judge 

 it in relation to his main self's general ethical 

 ideals and duties to self and the community. 

 Thus intelledtualizing it, 'he can destroy it or 

 consciously subordinate it to some aim in har- 

 mony with the rest of his personality. By so 

 doing there is gain in power of will and in 

 personal coherence of the individual. But if 

 the morbid situation be too strong or the 

 mental self too weak, instead of thus assimilat- 

 ing the contentious element the mind may 

 shun and, so to say, endeavor to ignore it. 

 That way lies danger. The discordant factor 

 escaped from the sway of the conscious mintt 

 produces stress and strain of the conscious 

 self; hence, to use customary terminology, dis- 

 sociation of the self sets in, bringing in its 

 train those disabilities, mental or nervous or 

 both, which characterize the sufferer from 

 hysteria. The normal action of the mind is 

 to make ixp from its components one unified 

 personality. When we remember the manifold 

 complexity of composition of the human in- 

 dividual, can we observe a greater example of 

 solidarity of working of an organism than that 

 presented by the human individual, intent and 

 concentrated, as the phrase goes, upon some 

 higher act of strenuous will? Physiologically 

 the supreme development of the brain, psycho- 

 logically the mental powers attaching thereto, 

 seem to represent from the 'biological stand- 

 point the very culmination of the integration 

 of the animal organism. 



The mental attributes of the nervous sj'stem 

 would be, then, the coping-stone of the con- 

 struction of the individual. Sui'veyed in their 

 broad biological aspect, we see them carrying 

 integration even further still. They do not 

 stop at the individual; thej^ proceed beyond the 

 individual; they integrate, from individuals, 

 communities. When we review, so far as we 

 can judge it, the distribution of mind within 

 the range of animal forms, we meet two peaKs 

 of its development — one in insect life, the other 

 in the vertebrate, with its acme finally in man. 

 True, in the insect the type of mind is not 



