The impulses of the former are, therefore, superior to those of the latter.

But as the events are contrary, and it is impossible both these figures can be turned up; the impulses likewise become contrary, and the inferior destroys the superior, as far as its strength goes.

The vivacity of the idea is always proportionable to the degrees of the impulse or tendency to the transition; and belief is the same with the vivacity of the idea, according to the precedent doctrine.
SECT.XII.OF THE PROBABILITY OF CAUSES.
What I have said concerning the probability of chances can serve to no other purpose, than to assist us in explaining the probability of causes; since it is commonly allowed by philosophers, that what the vulgar call chance is nothing but a secret and concealed cause.

That species of probability, therefore, is what we must chiefly examine.
The probabilities of causes are of several kinds; but are all derived from the same origin, viz.

THE ASSOCIATION OF IDEAS TO A PRESENT IMPRESSION.