Is it not equally true, that it is only by our own mental consciousness that we are qualified to conceive of other minds, and that we are, to a certain extent, guided by analogy to the belief that our fellow-men are possessed, like ourselves, of intelligence and design?
But who would say that this conclusion is no more than a _probable_ conjecture, or that, depending as it does in part on the analogy of our own experience, it cannot yield absolute certainty?
In so far as it is _merely_ analogical, it might be only more or less probable; but being founded also on the law of causality, it is an inductive inference, and, as such, one of the most certain convictions of the human mind.
And so the argument derived from marks of design in Nature may be stated in one or other of two ways:--it may be stated _analogically_ or _inductively_.

The difference between analogy and induction, which is not always duly considered, should be carefully marked.

Analogy proceeds on _partial_, induction on _perfect_ resemblance.

The former marks a resemblance or agreement _in some respects_ between things which differ _in other respects_: the latter requires a strict and entire similarity _in those respects_ on which the inductive inference depends.

The one by itself may only yield a _probable_ conjecture, but the other, when combined with it, may produce a _certain_ conviction.