THE STABILITY OF TRUTH. 349 
If we can not find them, we do not know that they exist. 
If we do not mow that they exist, shall we delieve that 
they do? Is it not better, as Emerson suggests, that 
men should not “ pretend to know and believe what they 
do not really know and believe”? 
It may be that the present existence of life in a 
world once lifeless renders spontaneous generation a 
“logical necessity.” But the “logical necessity” ex- 
ists in our minds, not in Nature. Science knows no 
“logical necessity,” for the simple reason that we are 
never able to compass all the possibilities in any given 
case. 
If we are to apply philosophic tests to the theories 
of reincarnation, we may find them equally eligible as 
articles of belief. They are plausible, to 
some minds at least; they have logical 
continuity. They are satisfying to the human heart; 
at least this is claimed by their advocates. Their chief 
fault is that science knows nothing of them, and her 
inductions yield them no support. In other words, 
their only reality is that of the visions of dreamland. 
From the objective side their postulates and arguments 
have no existence. The whole thing is meaningless. If 
plausibility and acceptability serve as sufficient founda- 
tions for belief, then belief itself is a frail and transient 
thing, no more worthy of respect than prejudice, from 
which, indeed, it can not be distinguished. 
Haeckel recognises this difference clearly enough by 
using the term belief for “hypotheses or conjectures of 
more or less probability ” by which “the 
gaps empirical investigation must leave 
in science are filled up.” “These,” he 
says, “ we can not indeed for a time establish on a secure 
basis, and yet we may make use of them in the way of 
explaining phenomena, in so far as they are not incon- 
Reincarnation. 
Haeckel’s defini- 
tion of belief. 
