vidence from the past in favour of the laws of motion than we have
in favour of the sunrise, because the sunrise is merely a particular
case of fulfilment of the laws of motion, and there are countless other
particular cases. But the real question is: Do _any_ number of cases
of a law being fulfilled in the past afford evidence that it will be
fulfilled in the future? If not, it becomes plain that we have no ground
whatever for expecting the sun to rise to-morrow, or for expecting the
bread we shall eat at our next meal not to poison us, or for any of the
other scarcely conscious expectations that control our daily lives. It
is to be observed that all such expectations are only _probable_; thus
we have not to seek for a proof that they _must_ be fulfilled, but
only for some reason in favour of the view that they are _likely_ to be
fulfilled.

Now in dealing with this question we must, to begin with, make an
important distinction, without which we should soon become involved
in hopeless confusions. Experience has shown us that, hitherto, the
frequent repetition of some uniform succession or coexistence has been a
_cause_ of our expecting the same succession or coexistence on the next
occasion. Food that has a certain appearance generally has a certain
taste, and it is a severe shock to our expectations when the familiar
appearance is found to be associated with an unusual taste. Things which
we see become associated, by habit, with certain tactile sensations
which we expect if we touch them; one of the horrors of a ghost (in
many ghost-stories) is that it fails to give us any sensations of touch.
Uneducated people who go abroad for the first time are so surprised as
to be incredulous when they find their native language not understood.

And this kind of association is not confined to men; in animals also it
is very strong. A horse which has been often driven along a certain
road resists the attempt to drive him in a different direction. Domestic
animals expect food when they see the person who usually feeds them. We
know that all these rather crude expectations of uniformity are liable
to be misleading. The man who has fed the chicken every day throughout
its life at last wrings its neck instead, showing that more refined
views as to the uniformity of nature would have been useful to the
chicken.

But in spite of the misleadingness of such expectations, they
nevertheless exist. The mere fact that something has happened