n in it to make Himself known
to His intelligent creatures, we may infer, with some measure of
probability, that other worlds may also be inhabited by beings capable,
like ourselves, of admiring His works, and adoring His infinite
perfections; but if we go further, and infer either that all these
worlds must _now_ be inhabited, or that the inhabitants must be _in all
respects_ constituted as we are, we pass far beyond the point to which
our knowledge extends, and enter on the region of mere conjecture. And
so when Mr. Holyoake extends the analogy, so as to include not only the
marks of design, on which the inductive inference rests, but also the
forms of organization, with which in the case of man, intelligence is at
presented associated, although not identified, he goes beyond the point
at which analogy and induction combine to give a _certain_ conclusion,
and introduces a conjectural element, which may well render his own
inferences extremely doubtful, but which can have no effect in weakening
the grounds of our confidence in the fundamental law, which demands an
adequate cause for the marks of design in nature.

Mr. Ferrier has shown that "the senses are only _contingent conditions_
of knowledge; in other words, it is possible that intelligences
different from the human (supposing that there are such) should
apprehend things under other laws, or in other ways, than those of
seeing, hearing, touching, tasting, and smelling; or more shortly, _our_
senses are not laws of cognition or modes of apprehension which are
binding on intelligence necessarily and universally."--"A contingent law
of knowledge" is defined as "one which, although complied with in
certain cases in the attainment of knowledge, is not enforced by reason
as a condition which _must_ be complied with wherever knowledge is to
take place. Knowledge is thus possible under other conditions than the
contingent laws to which certain intelligences may be subject; in other
words, there is no contradiction in affirming that an intelligent being
may have knowledge of some kind or other without having such senses as
we have."[285]

The application of analogy as a principle of judgment is subject to
certain well-known limitations, which cannot be disregarded without
serious risk of error. They are well stated by Dr. Hampden: "There are
two requisites in order to every analogical argument:--1. That the two,
or several particulars concerned in the argument should be