WHAT IS A DISEASE? 229 



practice of medicine. In every calling, however, a time must 

 at length come when a definition of its fundamental concepts 

 is needed ; it may be to divide it from other callings ; it may 

 be to settle some question that lies near the boundary line ; 

 if may be for some purpose foreign to the calling itself. Such 

 a time is now arrived in the history of medicine. 



Owing to enactments casting upon other than injured or 

 sick persons the burden of their treatment and maintenance, 

 and of compensating the dependants of those who are killed, 

 there has grown up a great amount of litigation about medical 

 matters ; and as all decisions in law turn upon the meaning 

 of some word of phrase, it is not surprising that much of this 

 litigation turns upon the meaning of such words as injury, 

 accident, disease, functional disease, organic disease, imaginary 

 disease, and so forth. It was natural that law should turn 

 to medicine for definitions of these terms, terms that are used 

 daily and hourly in medicine, and without which the science 

 and art of medicine could not be carried on ; and law must 

 have been considerably surprised to find that medicine has 

 been using these terms for centuries without any clear formula- 

 tion of their meaning, a surprise which was no doubt none 

 the less for the fact, which law did not recognise, that some 

 of its own fundamental terms, such as motive and intention, 

 were equally wanting in definite formulation. The time is 

 now come when some definition of the fundamentals of medi- 

 cine must be found. The definitions that I shall propose 

 may not be perfect, but at least they do render more clear 

 the fundamental concepts of medicine that are at present 

 nebulous and inchoate, and they are supported by reasons 

 that it is open to any one to question and refute if they are 

 unsound. From the tyro to the veteran, every medical prac- 

 titioner speaks and thinks scores of times every day of symp- 

 toms and of diseases, and has some vague notion in his mind 

 that there is a difference between a symptom and a disease ; 

 but what that difference is, no doctor can tell. I think this 

 inability is a reproach to medicine, and I shall try in what 

 follows to remove it. 



The human body, as conceived by the physician and the 

 surgeon — the alienist has, or ought to have, a very different 

 concept of it — is a very complex mechanism, composed of 

 many parts, each of which performs a certain duty towards 



