xii INTRODUCTION 



It was the " what happens ? " which interested these older 

 workers : 4 ' Why it happens ? " was generally beyond them, and 

 vague theories of some peculiar and special vital action took the 

 place of actual demonstration. 



Undoubtedly the association of physiology with the more 

 exact science of physics, based as it is so largely upon mathe- 

 matics, has had an enormous effect in getting rid of this habit 

 of vague theorising and has materially helped to clarify minds 

 " debauched with the so-called science of biology " as Tait, in 

 the early eighties, was wont to describe our mental condition. 



It has also stimulated the critical faculty, which insists upon a 

 clear proof and demonstration as a basis of conclusions. 



It is much to be regretted that even at the present time the 

 importance of a mathematical training, so essential for the study 

 of physics, is not generally recognised, and that it is still possible 

 to take a higher degree in science without this necessary prepara- 

 tion. 



It has been through the co-operation of physics and chemistry 

 that the solution of many of the problems of life have been 

 reached, and as the possibility of reaching these solutions has 

 become more generally recognised, the spirit of scientific curiosity 

 the desire to know, which is the basis of all scientific work 

 has been stimulated ; although probably in the future as in the 

 past, humanity will still be divided into the enormously large 

 class of those who have no real desire to understand the workings 

 of nature and the very small class of those who have the spirit of 

 curiosity, who do desire to know. These alone are the scientists, 

 although many science graduates belong to the major class. 



With or without any wider diffusion of the spirit of curiosity, 

 the development of the critical faculty and the better training 

 of the younger workers in physics and chemistry has brought 

 physiology nearer to the position of an exact science, and with 

 this, its value as a training for students of medicine has greatly 

 increased. The doctor, in making a diagnosis, has not merely 

 to observe and record what has happened, but he must ascertain 

 why it has happened. His problems are the same in nature and 

 his methods are the same as those of the physiologist, and thus 

 physiology has regained its position as the Institutes of Medicine. 



The doctor of the past considered that he had made a diagnosis 

 when he was able to give his patient's disease a name. The 

 physician of the future will care less and less for such names. He 

 will simply be concerned with the solution of the questions 



