A man, who gives orders for his dinner, doubts not of the obedience of his servants.

In short, as nothing more nearly interests us than our own actions and those of others, the greatest part of our reasonings is employed in judgments concerning them.

Now I assert, that whoever reasons after this manner, does ipso facto believe the actions of the will to arise from necessity, and that he knows not what he means, when he denies it.
All those objects, of which we call the one cause and the other effect, considered in themselves, are as distinct and separate from each other, as any two things in nature, nor can we ever, by the most accurate survey of them, infer the existence of the one from that of the other.
It is only from experience and the observation of their constant union, that we are able to form this inference; and even after all, the inference is nothing but the effects of custom on the imagination.

We must not here be content with saying, that the idea of cause and effect arises from objects constantly united; but must affirm, that it is the very same with the idea of those objects, and that the necessary connexion is not discovered by a conclusion of the understanding, but is merely a perception of the mind.

Wherever, therefore, we observe the same union, and wherever the union operates in the same manner upon the belief and opinion, we have the idea of causes and necessity, though perhaps we may avoid those expressions.