352 FOOT-NOTES TO EVOLUTION. 
least equally well equipped to pass judgment on such 
speculations as their advocates.” 
In other words, if any of these systems of philosophy 
are to descend from cloudland to be wrought into hu- 
man action, they must enter the domain of science and 
submit themselves to scientific tests. 
Again, if we are to allow the revision of the generali- 
zations of science by the addition of acceptable but un- 
verified doctrines, we must allow the 
right of similar revision by rejection. 
Mr. Wallace, for example, would be 
justified in adding to the certainties of 
organic evolution his idea of the special creation of the 
mind of man while the body was separately developed 
under natural law. The old notion of the separate ex- 
istence of the ego, which plays on the nerve cells of the 
brain as a musician on the keys of a piano, would still 
linger in psychology. The astral body would hover on 
the verge of physiology, and a strong plea would go up 
for the reality of Santa Claus. 
I have a scientific friend who finds it necessary to 
exclude by force from his biological beliefs all that is 
unpleasant in the theories of evolution. And he has the 
same right to do this that Professor Haeckel has to insist 
that any scientific beliefs, for which science has yet no 
warrant, are a necessary part of the orthodoxy of science. 
For Haeckel is not content to speak for himself, 
asking tolerance by tolerance toward others. His be- 
lief is no idiosyncrasy of his own. He speaks for all. 
Every honest, intelligent, courageous scientific man, he 
tells us, so far as he is truthful, competent, and brave, 
shares the same belief. His confession of faith is 
nothing if not orthodox. He says: 
“This monistic confession has the greater claim to 
an unprejudiced consideration in that it is shared, I am 
Revision of 
science by 
philosophy. 
