rison of ideas. By proofs,
those arguments, which are derived from the relation of cause and
effect, and which are entirely free from doubt and uncertainty. By
probability, that evidence, which is still attended with uncertainty. It
is this last species of reasoning, I proceed to examine.

Probability or reasoning from conjecture may be divided into two kinds,
viz. that which is founded on chance, and that which arises from causes.
We shall consider each of these in order.

The idea of cause and effect is derived from experience, which
presenting us with certain objects constantly conjoined with each other,
produces such a habit of surveying them in that relation, that we cannot
without a sensible violence survey them iii any other. On the other
hand, as chance is nothing real in itself, and, properly speaking, is
merely the negation of a cause, its influence on the mind is contrary to
that of causation; and it is essential to it, to leave the imagination
perfectly indifferent, either to consider the existence or non-existence
of that object, which is regarded as contingent. A cause traces the
way to our thought, and in a manner forces us to survey such certain
objects, in such certain relations. Chance can only destroy this
determination of the thought, and leave the mind in its native situation
of indifference; in which, upon the absence of a cause, it is instantly
re-instated.

Since therefore an entire indifference is essential to chance, no one
chance can possibly be superior to another, otherwise than as it is
composed of a superior number of equal chances. For if we affirm that
one chance can, after any other manner, be superior to another, we must
at the same time affirm, that there is something, which gives it the
superiority, and determines the event rather to that side than the
other: That is, in other words, we must allow of a cause, and destroy
the supposition of chance; which we had before established. A
perfect and total indifference is essential to chance, and one total
indifference can never in itself be either superior or inferior to
another. This truth is not peculiar to my system, but is acknowledged by
every one, that forms calculations concerning chances.

And here it is remarkable, that though chance and causation be directly
contrary, yet it is impossible for us to conceive this combination of
chances, which is requisite to render one hazard superior to another,
without supposing a mixture of