PRESIDENT S ADDRESS. 719 
‘to be on a matter more or less connected with the purport 
-of this Section, and, outside my profession, I could by 
no means consider myself a professed hygienist. How- 
ever, after some deliberation, I decided in addressing you 
on “The Nature of Disease.”’ 
Sanitary Science is almost exclusively interested in 
the cause and prevention of disease, but to limit my 
remarks to the latter alone would have compelled me to 
adopt the tone of an expert in sanitation, which I have 
already told you I am not. Hygiene belongs equaity to 
the man in the street and to the full-fledged medical expert 
and the scientist... In fact, it is to the former that all 
interested in this branch of knowledge have to make their 
final appeal. We may deliberate and discuss, draw up 
proposals and suggest alterations; but to the Legislative 
Chamber we must finally come. There sit our masters, 
and they must be instructed ere they can be expected to 
pass the laws the skilled scientist suggests. As a matter of 
fact, in social science we stand on a different level from the 
one we occupy in relation to the public in the medical 
world. In the latter, the physician is authoritative. He 
can give his orders in military fashion; he has not to 
explain or to instruct. It matters little to him whether the 
patient understands the nature of his affection or the 
design of the treatment. But the public must be taught 
before they can act and give effect to the hygienist’s views. 
Therefore, in this Section, we speak to the general ear. We 
must elicit their appreciation; our terms must be those 
in vogue, and our language as non-professional as possible. 
In selecting the titie—‘‘The Nature of Disease ’—I 
remembered the advice of an old and valued friend, who, 
when once placed in the same position as I stand in, 
namely, that of speaking to an audience on a semi-pro- 
_ fessional subject, advised that the text should be as 
comprehensive and indeterminate as possible, connected 
—but only loosely—with the subject under review. In 
treating of the nature of disease, I can sail my barque in 
many waters. Its vagueness is attractive; it permits 
me to traverse many subjects over which from time to 
time I have had much cause to ponder, -especially when 
I recall to mind the many changes that have taken place 
in one lifetime, in the thoughts of those who direct the 
current and varying shades of medical opinion. 
Preventive medicine relates almost wholly to the 
causes of illness, and concerns the connection of man 
with his neighbour, not only in health, but in those 
aberrations from it which we call disease. These causes 
