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[Vol. IX., No. 212 



science. If we look upon tliese mysterious nerve- 

 cells as a community of reasoning individuals, 

 we should expect to find a division of labor among 

 them which should restrict more or less com- 

 pletely the physiological activity of each anatom- 

 ical area. What we know of the subject justi- 

 fies this comparison. We find the nerve-cells of 

 the medulla and spinal cord inheriting automatic 

 and reflex powers of comparatively simple char- 

 acter, but of vital importance to the life of the 

 whole system ; and there is reason to believe that 

 these powers are more extensive and efiicient the 

 longer they have been impressed by heredity. 

 When we ascend from the medulla to the cere- 

 bellum, we come upon powers of the same kind, 

 but vastly more complex in their co-ordinations ; 

 and here, or hereabouts, we meet a new faculty, — 

 that of learning reflexes, or learning to carry on a 

 complicated action with machine-like definiteness 

 and celerity in obedience to a given stimulus. The 

 complex motions of walking, balancing, the per- 

 formance of an experienced pianist, are largely re- 

 flexes whose centres, in all probability, lie in this 

 part of the brain. Then we gradually rise through 

 nerve-centre after nerve-centre, with graduated 

 physiological powers, till we reach the Teacher 

 himself, whose energy is, doubtless, that of the 

 cortical cerebral cells. Nothing is clearer in physi- 

 ology than this general differentiation of function 

 among the nerve-centres, and it is altogether proba- 

 ble that a physiological differentiation even goes 

 hand in hand with the morphological one which 

 histologists have shown to involve the matter mak- 

 ing up the individual animal cell itself. 



Looking at the cortical cells again as a com- 

 munity, we should expect that the complex of 

 powers of the society should be divided up and 

 portioned off to distinct individuals which should 

 inherit extreme facility of action in a definite 

 province without altogether losing the other, now 

 subordinated, functions with which they were 

 originally endowed. Artificial stimulation of 

 definite cortical areas we should expect to be 

 followed by a manifestation of their specific func- 

 tion ; and, on the contrary, annihilation of such a 

 region ought to be followed by a corresponding 

 paralysis, which would not be permanent, because 

 neighboring cells would gradually develop the 

 lost function, the power to perform which had 

 hitherto been latent in them. Each new lesion 

 would be followed by a crippling involving the 

 same features, and the recovery would each time 

 be less perfect. This presentation may be taken, 

 as far as the results go, as the actual outcome of 

 experimentation on the brain ; and the same his- 

 tory would be repeated by any civilized com- 

 munity in which the various trades and pro- 



fessions should, in turn, be deprived of their 

 workers. 



Physiological phenomena are those in which 

 the activities of various tissues are co-ordinated in 

 such a way as to produce a combined action ; and 

 we may consider each tissue-element as a reason- 

 ing individual which associates physiologically 

 with its neighbors only so far as a result of this 

 union is beneficial to its own welfare. 



Turning now from the normal body to view the 

 phenomena of pathology, we enter a field which 

 has been too incompletely surveyed for us to trace 

 our way at will in it ; but so far as pathological 

 processes are understood, they seem to be guided 

 by the same law of endeavor for self-aggrandize- 

 ment on the part of the living cells concerned, as 

 in those actions already considered. When an 

 arterial wall becomes cheesy or chalky in athe- 

 roma as a result of increased arterial strain, we see 

 living tissue-elements redeveloping some of their 

 suppressed embryonic powers of metabolism, and 

 replacing their sentient, overworked protoplasm by 

 an inert substance incapable of either evolving 

 energy or suffering from overstrain. Unfortunately 

 this ostrich-like hiding of the head is an ill-judged 

 attempt at self-preservation ; for it entails in- 

 creased labor on other organs, which may restdt in 

 fatal inco-ordination. So, also, when a foreign 

 particle within the body is encysted by an enve- 

 lope of tissue developed for that purpose, the 

 whole process goes on as if the active cells had 

 distinctly in view the covering-up of a hurtfuUy 

 irritating object. 



Those pathological processes which are more 

 usual grade imperceptibly into the physiological ; 

 as, for instance, those phenomena of altered circu- 

 lation and growth attending the healing of the 

 fracture in a broken bone. 



Only a competent pathologist could give full 

 force to the proposition here stated : but there 

 seems to be convincing evidence that in pathologi- 

 cal as in physiological processes there is a distinct 

 effort, on the part of the acting protoplasm, towards 

 self-aggrandizement ; that is, to reduce its expen- 

 diture and to increase its income of energy. In 

 the physiological process the various factors work 

 together in such a way that the resultant effort is 

 of the greatest possible benefit to each separate 

 member without detriment to any other. In an 

 extreme pathological action the selfishness of some 

 single individual brings ruin on the whole organ- 

 ism, because regardless of the fact that unlimited 

 self-aggrandizement is hurtful to the remainder of 

 the community. We may profitably compare 

 these two biological conditions to the states of dis- 

 cipline on shipboard as they may be observed 

 respectively in calm weather and during great 



