198 
lies wholly outside its domain. The point I want to insist on 
is, that unless we . see indications of growth from a previous 
different state, we have no right to assume that the question 
belongs to the domain of science at all, or to reject the 
alternative supposition. 
These examples taken from the physical division of natural 
science were intended to lead on to the consideration of cer- 
tain questions arising in the other, the biological, branch 
which have of late years excited a great deal of attention, and 
with which, from a theological point of view, we are more 
nearly concerned. 
Naturalists recognise an enormous number of so-called 
species of plants and animals. It is true that the distinction 
between a species and a mere variety is often doubtful ; for 
though species admits of a theoretical definition, the working 
out of that definition experimentally involves so much time 
and patience that practically we are left to reason by analogy 
of what we do happen to know in similar cases. Where some 
general resemblance is combined with differences greater than 
such as our experience warrants us in attributing to mere 
breed, we are obliged to regard the individuals as belonging 
to different species; but inasmuch as this is a conclusion 
depending on lack of evidence to the contrary, and the 
evidence we have is far short of that which it is conceivably 
possible to obtain, it is clear that the tendency must be 
towards the multiplication of species. But, with every allow- 
ance for such multiplication, it is evident that the number of 
species will be enormously great. And, large as is this number 
already, it is very greatly increased when we include the 
plants and animals of past ages which, or more probably only 
a portion of which, are preserved to us in a fossilised state. 
The question then naturally arises, How came this great 
number of species to be as they are ? Are we obliged to 
suppose that each member of this vast array originated in an 
isolated and independent creative act ; or may we regard the 
observed condition as naturally evolved under the operation of 
laws either known, or conceivably open to scientific investiga- 
tion, from some preceding condition of a simpler character ? 
There is nothing at all atheistic in proposing the latter 
question, or in answering it in the affirmative in case we should 
find reasonable scientific evidence in favour of an affirmative 
answer. It is a different thing altogether to assume a 'priori, 
independently of any evidence, that such must havebeen the case. 
For, if this were allowable, had we a right to assume that the 
present condition A must have grown naturally out of a different 
preceding condition B, then by parity of reasoning we should. 
