350 FOOT-NOTES TO EVOLUTION. 
sistent with a rational knowledge of Nature.” ‘Such 
rational hypotheses,” he says, “are scientific articles of 
faith.” It is not clear, however, that so large a name as 
faith need be taken for working hypotheses confessed- 
ly uncertain or transient, The words “make-believe,” 
used by Huxley in some such connection, might well be 
applied to hypothetical “ articles of faith’ which have no 
basis in scientific induction. But it seems to me that 
it is not necessary for the man of science to say “I be- 
lieve” in addition to “I know.’’ He should not “be- 
lieve” where he can not trust. He should put off the 
livery of science when he enters the service of the Del- 
phian oracles. 
That all the doctrines above mentioned are neces- 
sarily included in monism, may perhaps be doubted. 
Monism would probably still flourish were all these 
theories disproved; for human philosophies have won- 
derful recuperative power. Their basis is in the struc- 
ture of the brain itself, and external phenomena are 
only accessory to them. 
If monism is a purely philosophic conception, it can 
have no necessary axioms or corollaries, except such as 
are involved in its definition. These could not be scien- 
tific in their character, because they could in no way 
come into relation with the realities of human life. If, 
however, monism be a generalization, resting in part on 
human experience, then it must be tested by the meth- 
ods of science. Until it is so tested, however plausible 
it may seem, it has no working value. There is no gain 
in giving it belief or in calling it truth. 
Still less should we stultify ourselves by 
pinning our faith to its postulates as to 
matters yet to be decided by experiment 
and to be settled by human experiment only. Haeckel 
says, for example: “The inheritance of characters ac- 
The inheritance 
of acquired 
characters. 
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