8 
ORGANIC DEPENDENCE AND DISEASE 
is a pathological condition involving the normal growth of a 
living creature, the Bacillus tuberculosis. This condition 
is a disease only from the point of view of the host of the- 
parasite, that is, of the sufferer. To the parasite it is the 
normal, though adjusted, mode of life. This, however, is 
an advanced and complicated example whose history, when 
worked out, must be determined on the basis of causes pro- 
ducing such adaptation of parasite to host, and the study 
of such adaptations must always keep in view the ease with 
which adaptations have constantly been and are constantly 
being made. Let us discuss this matter more at length. 
WHAT IS DISEASE? 
We must answer this question in terms of the original 
use of the word — disease is discomfort ; it is thus the early 
English writers employed it and we must not forget this 
simple meaning which is not observed in common usages. 
But in the specific application of the term to physical dis- 
comfort we shall find Huxley’s definition broad and clear: 
“Disease . . . is a perturbation of the normal activities 
of a living body.” In this expression by the great Eng- 
lish physiologist there is a definite implication that disease 
means disorder of specific function , as we generally under- 
stand it. But the broader idea in this definition is clear; 
that disease is any departure from normal living. It may 
be a departure in a single function or it may involve several 
functions of physiology; and such an abnormal condition 
may permeate so many functions as to create a general im- 
pairment or maladjustment of the entire anatomical ma- 
chinery. It is elementary, as well as scriptural, to say that 
seldom can one organic function become impaired without 
involving others, for no member of the body can say to 
another, 4 ‘ I have no need of thee. ’ ’ 
There is, however, a still broader conception that we can 
draw from Huxley’s definition and which is of the first im- 
