JULY 7, 1899. ] 
fication for each of these groups. One has 
‘only to read any accepted text-book of phys- 
iology or pathology to see that it is abso- 
lutely true that the narrow or anthropo- 
morphic view is the typical medical view. 
The medical man may learn from the zool- 
ogist and botanist, who have depended 
chiefly upon the comparative method for 
their most important results. Science can- 
not be hampered by any conventional re- 
striction ; it must be free to turn in every 
‘direction in which a discovery is possible. 
Now, medicine places a conventional restric- 
tion around the medical sciences, for by 
‘custom and precedent it orders that, even 
though the actual investigation be upon 
some animal, it shall be regarded solely as 
elucidating human structure and human 
function—in other words, the interpretation 
must be anthropomorphic. This conven- 
tion has led to some strange absurdities, of 
which I shall mention only one; the micro- 
scopic structure of the kidney has been in- 
vestigated chiefly in animals, notably the 
dog and rabbit; all the text-books of an- 
atomy and histology known to me, with a 
solitary exception, describe the structure of 
the human kidney in accordance with the 
observations on these animals ; but, as the 
human kidney really differs in many im- 
portant respects from that of the dog and 
the rabbit, the structure of the human kidney 
still remains generally unknown. ‘This 
error has been perpetuated through fifty 
years. Since zoologists are habituated to 
the comparative method, would it not be 
wholly impossible for a blunder of this kind 
to be kept up in their work ? 
I am so thoroughly convinced of the 
value of the comparative method, of the 
absolute necessity of its adoption in medical 
research, that I look forward to its accept- 
ance as the greatest advance in medicine 
which our time will know. Methods of 
obtaining knowledge are the means of prog- 
ress. Remember how much anatomy owes 
(SCIENCE. 7 
to the method of human dissection ; how 
much pathology owes to the method of stain- 
ing microscopical preparations ; how much 
surgery owes to the method of antisepsis ; 
how much bacteriology owes to the method 
of artificial cultures. These are, however, 
merely technical methods, but that which I 
am now advocating is a mental method, a 
way of successful thinking, a process of 
right reasoning, far more comprehensive 
than any technical method ; and, if we 
accept it, we can explore vast regions of 
knowledge, the very possibilities of which 
we barely recognize now. ' Let it encourage 
us that the comparative anatomist and com- 
parative embryologist are already well ad- 
vanced along the path which the physi- 
ologist and pathologist must now learn to 
follow. 
Medicine is destined to become compara- 
tive, because it must advance. The wise 
action for us is to facilitate that advance, 
and thus the question becomes: What shall 
we do practically to establish and promote 
comparative medicine? If we agree that 
our aim is to secure the very best kind of 
research in medical science the practical 
answer is clear: We must provide post- 
graduate instruction, with courses thor- 
oughly systematized and correlated, cover- 
ing at least two years, to qualify men to 
become professional investigators in the 
comparative sciences of morphology, physi- 
olozy, pathology, bacteriology, preventive 
medicine, etc. It is remarkable that these 
sciences have never reached a university 
standing. It ought now to be secured. If 
a young man wishes to make a scientific 
career, if his interest is chemistry, physics, 
botany or zoology, he is received at one of 
our universities started upon a well-planned 
course properly systematized, he gives for 
two or three years most of his strength to 
his main subject, but he follows probably 
two cognate subjects as minor studies, and 
at the end of his time, if successful in his 
