Here then are two particulars, which we are to consider as essential to necessity, viz, the constant union and the inference of the mind; and wherever we discover these we must acknowledge a necessity.

As the actions of matter have no necessity, but what is derived from these circumstances, and it is not by any insight into the essence of bodies we discover their connexion, the absence of this insight, while the union and inference remain, will never, in any case, remove the necessity.

It is the observation of the union, which produces the inference; for which reason it might be thought sufficient, if we prove a constant union in the actions of the mind, in order to establish the inference, along with the necessity of these actions.

But that I may bestow a greater force on my reasoning, I shall examine these particulars apart, and shall first prove from experience that our actions have a constant union with our motives, tempers, and circumstances, before I consider the inferences we draw from it.
To this end a very slight and general view of the common course of human affairs will be sufficient.

There is no light, in which we can take them, that does nor confirm this principle.