1894.] The Scope of Modern Physiology. 387 
physiological research, especially when our science is con- 
trasted with the other great division of biology. It is as if 
men had been nauseated by the vitalistic doctrines and other 
wild guesses of the past and had resolved hereafter to hold 
strictly to the Baconian method. At the risk of being misun- 
derstood and criticised, I cannot help feeling that this is to 
be deplored. The method of all physical science is truly 
observation and experiment; facts must be discovered and 
grouped and the laws formulated therefrom. But, in the 
search after facts, the inestimable value of hypothesis—of 
speculation, if you will—cannot be denied. It directs the 
searcher along a definite path and gives for the time being an 
encouraging and stimulating coherence to his results. If later 
his speculation becomes verified, well; if it proves false, its use 
is not to be deprecated, for it has served its purpose as an aid 
to discovery. The facts still remain, science is by so much 
the gainer, and with a new interpretation and a new hypoth- 
esis nearer the truth further advance will be made. The 
trouble is to keep the speculation within rational bounds and 
to know when to give it up. To employ it too sparingly is to 
retard scientific progress, and it seems to me that just here the 
animal physiologists of the present period are open to criti- 
cism. 
Further, it is to be noted that until far into this period 
throughout the Continental, the English, and most of the 
American universities physiology and anatomy have together 
formed one department. At Bonn from 1826 to 1833, and at 
Berlin from 1833 until his death in 1858, Müller occupied 
such a common chair. Helmholtz held a similar position in 
Bonn from 1855 until 1858. Now, everywhere, animal physi- 
ology presupposes anatomy, and each science has its own field 
and its own methods. Further still, physiology usually occu- 
pies a place in the Medical faculty. This also is the result of 
its historical development. As I have shown, it is to the med- 
ical fraternity, more than to any other one class, that 1t owes » 
its great progress in the past. But a glance at the literature 
of the present period will show that, largely through the efforts 
of its medical promoters, it has widely overstepped its early 
