sive part of its
own nature, and which, by showing to us that things are
not necessarily connected in fact because their ideas
are connected in our minds, is able to loosen
innumerable associations which reign despotically over
the undisciplined mind; this habit is not without power
even over those associations which the philosophical
school, of which I have been speaking, regard as connate
and instinctive. I am convinced that any one accustomed
to abstraction and analysis, who will fairly exert his
faculties for the purpose, will, when his imagination
has once learned to entertain the notion, find no
difficulty in conceiving that in some one, for instance,
of the many firmaments into which sidereal astronomy now
divides the universe, events may succeed one another at
random, without any fixed law; nor can any thing in our
experience, or in our mental nature, constitute a
sufficient, or indeed any, reason for believing that
this is nowhere the case. The grounds, therefore, which
warrant us in rejecting such a supposition with respect
to any of the phenomena of which we have experience,
must be sought elsewhere than in any supposed necessity
of our intellectual faculties.

"As was observed in a former place, the belief we
entertain in the universality, throughout nature, of the
law of cause and effect, is itself an instance of
induction; and by no means one of the earliest which any
of us, or which mankind in general, can have made. We
arrive at this universal law by generalisation from many
laws of inferior generality. The generalising propensity
which, instinctive or not, is one of the most powerful
principles of our nature, does not indeed wait for the
period when such a generalisation becomes strictly
legitimate. The mere unreasoning propensity to expect
what has been often experienced, doubtless led men to
believe that every thing had a cause, before they could
have conclusive evidence of that truth. But even this
cannot be supposed to have happened until many cases of
causation, or, in other words, many partial uniformities
of sequence, had become familiar. The more obvious of
the particular uniformities suggest and prove the
general uniformity; and that general uniformity, once
established, enables us to prove the remainder of the
particu