brought against all the actual--and even all the possible--lines of
evidence in favour of evolution. Therefore I deem it desirable thus
early in our proceedings to place this argument from ignorance on its
proper logical footing.

If there were any independent evidence in favour of special creation as
a _fact_, then indeed the argument from ignorance might be fairly used
against any sceptical cavils regarding the _method_. In this way, for
example, Bishop Butler made a legitimate use of the argument from
ignorance when he urged that it is no reasonable objection against a
revelation, _otherwise accredited_, to show that it has been rendered in
a form, or after a method, which we should not have antecedently
expected. But he could not have legitimately employed this argument,
except on the supposition that he had some independent evidence in
favour of the revelation; for, in the absence of any such independent
evidence, appeal to the argument from ignorance would have become a mere
begging of the question, by simply assuming that a revelation had been
made. And thus it is in the present case. A man, of course, may quite
legitimately say, _Assuming that the theory of special creation is
true_, it is not for us to anticipate the form or method of the
process. But where the question is as to whether or not the theory _is_
true, it becomes a mere begging of this question to take refuge in the
argument from ignorance, or to represent in effect that there is no
question to be discussed. And if, when the form or method is
investigated, it be found everywhere charged with evidence in favour of
the theory of descent, the case becomes the same as that of a supposed
revelation, which has been discredited by finding that all available
evidence points to a natural growth. In short, the argument from
ignorance is in any case available only as a negative foil against
destructive criticism: in no case has it any positive value, or value of
a constructive kind. Therefore, if a theory on any subject is destitute
of positive evidence, while some alternative theory is in possession of
such evidence, the argument from ignorance can be of no logical use to
the former, even though it maybe of such use to the latter. For it is
only the possession of positive evidence which can furnish a logical
justification of the argument from ignorance: in the absence of such
evidence, even the negative value of the argument disappears, and it
then implies