DIVERSITY OF SELECTION THROUGH DIVERSITY OF USE. 197 
active and passive selection, and under passive selection I place 
natural and artificial selection. Selection depending on the relations 
of the members of a species to each other I call reflexive selection, the 
chief forms of which I call conjunctional, dominational, impregna- 
tional, and institutional selection.* 
(4) It must be carefully noted that diversity of selection depending 
on diversity in the relations of the organism to the environment does 
not necessarily involve the exposure of the organism to different 
environments. In other words, change in even environal selection 
does not necessarily involve either change in the environment or the 
entrance of the species into a new district. Darwin’s teaching seems, 
at times, to be in conflict with this statement, but there are passages 
in his writings which distinctly state that variations in instinct may 
lead to different habits of sustentation, and it is evident that this 
would naturally lead to a difference in the congenital qualities that 
win success in the different sections and so to difference in the envi- 
ronal selection. 
It should be remembered, however, that the meaning of anyone’s 
statements on this subject will depend on his definitions of the words 
used. What is meant by environment, external conditions, and 
other similar terms? Until we define we shall only beat the air, how- 
ever exact our statements may seem tobe. I therefore repeat what 
I have elsewhere stated, that, according to my definition, change in 
the environment is always change in activities that lie outside of the 
species, or of the segregated group, of individuals that is under 
consideration. In Darwin’s usage the phrase ‘‘change in external 
conditions”’ seems to carry the same meaning; but in some cases this 
can hardly be the case. 
Diversity in the uses to which isolated sections of one species put 
their powers, when appropriating resources from the same environ- 
ment, must produce diversity in the forms of variation that are most 
successful in the different sections. This I call active selection as con- 
 trasted with passive selection, which varies according to differences 
in the environments.t All diversities of environal selection that do 
not vary according to differences in the environments must be classed 
as diversities of active selection, for they must have originated in 
some variation in the powers of the organism or in the diversity of 
uses to which it has put its powers. Diversity in the successful use 
of the powers of the species in dealing with the environment, whether 
* To these I now add prudential selection. 
+ For ‘‘active” and ‘‘passive’’ selection, I often substitute ‘‘endonomic” and 
‘“‘heteronomic’”’ selection. 
