A System of Logic: Ratiocinative and Inductive, 7th Edition, Vol. I
John Stuart Mill · en
Whatever be the most proper mode of expressing it, the proposition that
the course of nature is uniform, is the fundamental principle, or
general axiom, of Induction. It would yet be a great error to offer this
large generalization as any explanation of the inductive process. On the
contrary, I hold it to be itself an instance of induction, and induction
by no means of the most obvious kind. Far from being the first induction
we make, it is one of the last, or at all events one of those which are
latest in attaining strict philosophical accuracy. As a general maxim,
indeed, it has scarcely entered into the minds of any but philosophers;
nor even by them, as we shall have many opportunities of remarking, have
its extent and limits been always very justly conceived. The truth is,
that this great generalization is itself founded on prior
generalizations. The obscurer laws of nature were discovered by means
of it, but the more obvious ones must have been understood and assented
to as general truths before it was ever heard of. We should never have
thought of affirming that all phenomena take place according to general
laws, if we had not first arrived, in the case of a great multitude of
phenomena, at some knowledge of the laws themselves; which could be done
no otherwise than by induction. In what sense, then, can a principle,
which is so far from being our earliest induction, be regarded as our
warrant for all the others? In the only sense, in which (as we have
already seen) the general propositions which we place at the head of our
reasonings when we throw them into syllogisms, ever really contribute to
their validity. As Archbishop Whately remarks, every induction is a
syllogism with the major premise suppressed; or (as I prefer expressing
it) every induction may be thrown into the form of a syllogism, by
supplying a major premise. If this be actually done, the principle which
we are now considering, that of the uniformity of the course of nature,
will appear as the ultimate major premise of all inductions, and will,
therefore, stand to all inductions in the relation in which, as has been
shown at so much length, the major proposition of a syllogism always
stands to the conclusion; not contributing at all to prove it, but being
a necessary condition of its being proved; since no conclusion is
proved, for which there cannot be found a true major premise.[9]