OF PROBABILITY[9].

[9] Mr. Locke divides all arguments into demonstrative and
probable. In this view, we must say, that it is only probable
all men must die, or that the sun will rise to-morrow. But to
conform our language more to common use, we ought to divide
arguments into _demonstrations_, _proofs_, and _probabilities_.
By proofs meaning such arguments from experience as leave no
room for doubt or opposition.


46. Though there be no such thing as _Chance_ in the world; our
ignorance of the real cause of any event has the same influence on the
understanding, and begets a like species of belief or opinion.

There is certainly a probability, which arises from a superiority of
chances on any side; and according as this superiority encreases, and
surpasses the opposite chances, the probability receives a
proportionable encrease, and begets still a higher degree of belief or
assent to that side, in which we discover the superiority. If a dye were
marked with one figure or number of spots on four sides, and with
another figure or number of spots on the two remaining sides, it would
be more probable, that the former would turn up than the latter; though,
if it had a thousand sides marked in the same manner, and only one side
different, the probability would be much higher, and our belief or
expectation of the event more steady and secure. This process of the
thought or reasoning may seem trivial and obvious; but to those who
consider it more narrowly, it may, perhaps, afford matter for curious
speculation.