1896.] “ A New Factor in Evolution.” 709 
force in evolution above all other forces. It acts upon every 
external stimulus, interrupts and transforms its natural effect, 
molds and remolds the entire organism and all subsequent 
species in accord with the non-physical and miraculous power. 
If such a factor be admitted so dominantly throughout nature 
then exact science becomes absolutely impossible. 
Our examination of this “ New Factor” may, therefore, now 
_be summarized as follows. It is obvious, historically, how its 
ancient traditions, rooting originally in superstition, have 
survived and come down to be an anomaly in our scientific 
times. It never had any closer foundation in facts than the 
superficial observation that pleasure more often comes with 
health and strength, and pain with weakness and disease. The 
central neural processes on which it is alleged to be based do 
not exist. The phenomena in question, upon examination, 
flatly contradict at every point the assumptions and assertions 
boldly made of them. The alleged “ Factor,” if carried out un- 
der these assumptions and specifications so made of it, quickly 
reduces the entire realm of biology and of psychology to end- 
less confusion and ridicule. 
On the other hand these phenomena have now been treated 
of substantially without violating the symmetries of nature, 
and in accord with the obvious demands and analogies of the 
remainder of ascertained knowledge. Pain-nerves have been 
conclusively demonstrated. Pleasure and displeasure, if they 
have not been so successfully disposed of as bodily pain, have 
been finally divorced- from it and from the tradition that 
they are “ quality activities” of any kind; they are rapidly 
being driven by new analysis and definitions to where they are 
seen to be forms or movements of thought quite independent 
of specific qualitative make-up; are being explained on the 
same footing and in the same categories with conceptions, voli- 
tions and similar mental processes, which apparently may be 
of any and every “ quality,” or, at least, in which the qualities 
of the content play no at ptesent determinable part. 
Nor have these things been done in a corner. Modern litera- 
ture is full of them. These new opinions have been put for- 
