12- THE PRESIDENTIAL ADDRESS. 



of his mentality from examination of the relative development of the 

 several brain regions, using a true and scientific phrenology. 



Could we look quite naively at the question of a seat for the mind 

 within the body we might perhaps suppose it diffused there, not localised 

 in any one particular part at all. That it is localised and that its locali- 

 sation is in the nei-vous system — can we attach meaning to that fact? 

 The nervous system is that bodily system whose special office from its 

 earliest appearance onward throughout evolutionary history has been 

 more and more to weld together the body's component parts into one 

 consolidated mechanism reacting as a unity to the changeful world about 

 it. It more than any other system has constructed out of a collection 

 of organs an individual of unified act and experience. It represents the 

 acme of accomplishment of the integration of the animal organism. 

 That it is in this system that mind, as we know it, has had its begin- 

 ning, and with the progi'essivo development of the system has step for 

 step developed, is surely significant. So is it that in this system the 

 portion to which mind transcendcntly attaches is exactly that where are 

 carried to their highest pitch the nei-ve-actions which manage the indi- 

 vidual as a whole, especially in his reactions to the external world. 

 There, in the brain, the integrating nervous centres are themselves 

 further compounded, inter-connected, and re-combined for unitary func- 

 tions. The cortex of the forebrain is the main seat of mind. That cortex 

 with its twin halves con'esponding to the two side-halves of the body is 

 really a single organ knitting those halves together by a still further knit- 

 ting together of the nervous system itself. The animal's great integi'at- 

 ing system is there still further integi'ated. And this supreme integrator 

 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 begin- 

 nings it has become steadily a larger and larger feature of the nervous 

 system, until in adult man the whole rest of the system is relatively 

 dwarfed by it. Not without significance, perhaps, is 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 nervous focus unifying such 

 motor function will, in regard to a laterally bipartite organ, tend more 

 to one half or the other. 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 learn in full the con- 

 tribution made to the integration of the animal individual by mind. 

 But each of us can, without being a professed psychologist, yet recog- 

 nise one achievement in that direction which mental endowment has 

 produced. Made up of myriads of microscopic cell-lives, individually 

 born, feeding and breathing individually within the body, each one 



