An introductory text-book of logic - Mellone, Sydney - Rare Books at ...

THE GENERAL NATURE OF INDUCTION. 253
"
of Nature
Jevons speaks of the
"
Uniformity as
liable to exceptions; asking, for example, whether we
can be
"
certain that the sun will rise again to-morrow
morning, as it has risen for many thousand years, and
probably for some hundred million years." To answer
this question we must make an important distinction
between two meanings of the Uniformity of Nature :
(i) the Uniformity of Causation, (2) the maintenance
of the present order of things in the universe. Ex
perience shows us that there are general "laws"
i.e.,
kinds of orderly succession in the phenomenal course of
events : such as appear in the succession of day and
night, summer and winter, seed-time and harvest, life
and death. The regular succession of events in a
thousand different ways accustoms us, from force of
habit, to expect things to happen in a regular order;
and we find that the expectation is fulfilled. This
constitutes an overwhelming presumption
in favour of
the maintenance of the present arrangements in Nature ;
but it does not show that deviations from this order are
impossible. An expectation, bred by experience and
custom, that events will occur in a certain way
is not
the same as a knowledge that they must so occur ; and
this knowledge is not in our possession. We have no
grounds for affirming
that the sun must rise to-morrow
morning ; there is only an overwhelming presumption
in favour of the expectation that it will. But the
principle of Uniform Causation tells us nothing
the permanence of the present
as to
"choir of heaven and
furniture of earth." It only says that the same cause
will have the same effect ; and to this there are no
exceptions. The same cause may conceivably never
act again ; but this does not affect the truth of the
principle that if
it did it would have the same effect.