fif. 



DISCOVEHY 



ran be no mean occupation to \>c an artificer in an 

 edifice the foundation-stones of whirli were laid before 

 I'ytliagoras lived. Here there is work for the mediocre 

 as well as the talented ; as Russell puts it : " The 

 edifice of science needs its masons, bricklayers, and 

 common labourers as well as its foremen, master- 

 builders, and architects. In art nothing worth doing 

 can be done without geniuc ; in science even a moderate 

 capacity can contribute to a supreme achievement."' 



The reader may study the subject further in Mathematical 

 Recreations and Problems, by W. W. Rouse Ball. Eighth 

 edition. (Macmillan, 12s. 6d.) A fascinating book. 



The Role of Physiology' 

 in National Life 



By A. V. Hill, Sc.D., F.R.S. 



Professor of Physiology in tlw Unii'ersilij of Manchester 



Hitherto Physiology has had two roles, that of an 

 abstract science devoted to the elucidation of problems 

 provided b}' the living creature, and that of the hand- 

 maid of medicine attempting to describe the normal 

 healthy functions which medicine has to restore after 

 they have gone wTong. The physiologist, therefore, 

 had to earn a living either as a student and teacher in 

 a universit}', or as a practising medical man. To these 

 two roles is now being added a third, which we will pro- 

 ceed to describe — that of a student and investigator of 

 the human or biological factor in the social, economic, 

 or industrial system. 



It is obvious that in the last resort our political and 

 social system rests upon the mental and bodily charac- 

 teristics of its unit, MAN, and that these in the aggre- 

 gate depend largely on heredity and environment, and 

 not merely on fortuitous factors. The exact degree to 

 which the behaviour and the bodily, mental, and 

 moral " fitness " of men depend upon environment 

 and heredity is not yet known, possibly not knowable : 

 it is certain, however, that, within limits, " fitness " 

 and efficiency depend upon adequate training and 

 nutrition, and mental, moral, and bodily health on 

 heredity and example as well as on environment. 

 Further, it is obvious that a man's natural powers fit 

 him usually more for one trade than another, and that 

 it ought to be possible often to state in precise terms 

 w-hat that trade should be. Hitherto selection, both in 

 national and in individual life, has been left to nature, 



' Science and Culture. 



• To avoid a cumbrous form of expression, " I'hysiology " 

 is used here to denote the study of all the normal processes of 

 the animal, including those usually de.scribed as psychological. 



and man has progressed slowly and unconsciously 

 towards an unknown goal. Recently, however, he 

 has taken upon himself so largely to control, by under- 

 standing, the forces of nature, that a whole new crop 

 of problems is springing up insistently around him. 

 Large urban populations have arisen as a result of the 

 conquests of hygiene and engineering ; plagues have 

 been abolished by the discoveries of medicine ; famines 

 have been mitigated by facility of transport, and highly 

 skilled and specialised trades have arisen calling for a 

 new type of average man. Moreover, the coming of 

 some degree of general education and self-government, 

 together with the growth of class consciousness and 

 nationalism, have made it necessary to exercise the 

 utmost care in the applications of the science of man 

 as a biological unit. These applications, however, are 

 bound to come : man has taken upon himself to prevent 

 plagues and to mitigate famines, and he will shortly 

 have to limit population, to improve industrial 

 efficiency and to eliminate waste — or a worse thing 

 will befall him. All men get sick and die, and so 

 all pass within the purview of medicine : this is 

 inevitable, and there is little prejudice against regard- 

 ing the sick man as the " material " of medical science. 

 But many men, for the larger part of their lives, are 

 normal healthy individuals ; many others would have 

 been healthy had w-e made an adequate study of the 

 conditions required to maintain their efficiency in the 

 state of life to w-hich they have been caUed. These 

 men require, not medicine, but physiology, to discover, 

 develop and utilise their normal powers and functions 

 to the full, and to see that the lives they lead are of 

 the greatest benefit to themselves, to their neighbours, 

 and to their descendants. 



Nutrition, hours of work, standards of physical and 

 mental fitness of different types of population, recrea- 

 tions, physical training, vocational training, standards 

 of living, the effect of various habits and propensities 

 on the normal man, eugenics and what to breed for if we 

 could, these are among the many points at which the 

 economic and social problem touches on the biological 

 one. Physiology as yet can give no answer to these 

 problems, partly because of their inherent difficulty, 

 but largely because she has tended, with Medicine, 

 to regard the human factor from the bedside. It is 

 necessary to found a new profession, that of Physiology, 

 charged with the study of the biological factor in 

 normal human affairs. 



To take an example from the more purely ph\-sio- 

 logical side, the investigations of J. S. Haldane on the 

 respiratory conditions in mines, the experiments by 

 Hopkins on " accessory factors " in food, or the work 

 of the Anthropometric Standards Committee of the 

 Medical Research Council, are examples of the way in 

 which biology may come in immediate contact with 



