But it is from this resemblance, that the ideas of necessity, of power, and of efficacy, are derived.

These ideas, therefore, represent not anything, that does or can belong to the objects, which are constantly conjoined.

This is an argument, which, in every view we can examine it, will be found perfectly unanswerable.

Similar instances are still the first source of our idea of power or necessity; at the same time that they have no influence by their similarity either on each other, or on any external object.

We must, therefore, turn ourselves to some other quarter to seek the origin of that idea.
Though the several resembling instances, which give rise to the idea of power, have no influence on each other, and can never produce any new quality in the object, which can be the model of that idea, yet the observation of this resemblance produces a new impression in the mind, which is its real model.