What principally gives authority to this system is, beside the undoubted
arguments, upon which each part is founded, the agreement of these
parts, and the necessity of one to explain another. The belief, which
attends our memory, is of the same nature with that, which is derived
from our judgments: Nor is there any difference betwixt that judgment,
which is derived from a constant and uniform connexion of causes and
effects, and that which depends upon an interrupted and uncertain. It is
indeed evident, that in all determinations, where the mind decides from
contrary experiments, it is first divided within itself, and has an
inclination to either side in proportion to the number of experiments
we have seen and remember. This contest is at last determined to the
advantage of that side, where we observe a superior number of these
experiments; but still with a diminution of force in the evidence
correspondent to the number of the opposite experiments. Each
possibility, of which the probability is composed, operates separately
upon the imagination; and it is the larger collection of possibilities,
which at last prevails, and that with a force proportionable to its
superiority. All these phenomena lead directly to the precedent system;
nor will it ever be possible upon any other principles to give a
satisfactory and consistent explication of them. Without considering
these judgments as the effects of custom on the imagination, we shall
lose ourselves in perpetual contradiction and absurdity.
SECT. XIV. OF THE IDEA OF NECESSARY CONNEXION.