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SCIENCE 



[N. S. Vol. XLIX. No. 1266 



my first thesis, namely : that a patient is al- 

 ways changing, growing'. 



Johannis Bernoulli, a member of the most 

 remarkable family of mathematicians of which 

 we have a record, published in 1699 a thesis 

 in which he maintained the continual change 

 of substance of the body. 



His argument drew the theological lightning 

 of his day, and he forebore to push his studies 

 further, but his ideas were passed along, and 

 I know that in my youth no self-respecting 

 popular physiology failed to repeat the state- 

 ment that the human body underwent a com- 

 plete change of substance once in seven years. 



We look at matters somewhat differently to- 

 day but it is not without interest to record 

 that this idea of change started under such 

 eminent patronage. The modifications due to 

 growth are another matter, yet the idea of 

 growth, despite the universality of the phe- 

 nomenon, has been only gradually assimilated 

 and put to use. 



In earlier times growth was but little con- 

 sidered. We need not go back very far in 

 medical history to find that the typical patient 

 was the person already grown. The patient 

 was thus standardized. 



The young were dealt with by midwives and 

 grandmothers, and the aged took care of one 

 another. 



Speaking in the broadest way the physi- 

 cian's business was to care for that mythical 

 person, the average man, to whom the recorded 

 facts of anatomy and physiology all applied; 

 for the phases of growth were not then re- 

 garded in these disciplines, and medicine shared 

 with art and education a curious blindness to 

 developmental changes. Great advances have 

 occmrred. We now have those clinicians who 

 give special care to children, to adolescents 

 or to the aged. 



The relations of age to the incidence of dis- 

 ease, as in the children's diseases, in typhoid 

 or in cancer, have directed attention to pro- 

 gressive alterations within the individual, a 

 series of changes which are quite aside from 

 the marks of maturity or the signs of old age. 



Thus men of a given race pass through a 



series of well recognized phases and, as in a 

 set of dissolving views, infancy merges into 

 childhood and childhood is transformed to 

 youth, and so within the span of life we have 

 revealed the seven ages of man, so quaintly 

 sketched by Shakespeare. 



Familiar as these phases are it has taken no 

 small labor to bring them into the field of 

 practise and to have them recognized as of 

 clinical importance. There is the same diffi- 

 culty here that api)ears in carrying over to 

 our laboratory work the ideas of variability 

 and of graded relationship which were devel- 

 oped by Darwin and those who followed in 

 his steps. 



We know that individuals differ in their 

 form and anatomy, but we wish they didn't; 

 it would be so much easier if they were all 

 just alike. 



We know, too, that what is true of structure 

 is also true with regard to the functions of 

 the body. Here the facts are harder to ap- 

 praise, and there is a still stronger tendency 

 to dodge them. But this avails us nothing. 

 The facts will find us out — and moreover they 

 are unpleasantly immortal. 



The idea which I wish to drive home is 

 this: During the span of life the body shows 

 changes more or less like those shown by a 

 battered ship or neglected automobile, but be- 

 hind these lies a set of changes which no dead 

 structure or machine exhibits, a progressive 

 chemical alteration of the body linked with 

 age, probably affecting all its parts, and con- 

 stituting the series of modifications char- 

 acteristic for the individuals of any species, 

 as these pass from birth to senile death. 



The mechanism which prepares our food; 

 that which distributes the food-bearing blood; 

 the nervous system which controls our be- 

 havior; the muscles which do the work, and 

 the internal secretions from the ductless 

 glands and other sources which serve to tune 

 or tone our organs, all these undergo with 

 age changes not only in themselves but in 

 their relations to one another. 



On the balance of these component parts 

 depends that somewhat subtle character called 



