It has been observed, in treating of the understanding, that the distinction which we sometimes make betwixt a _power_ and the _exercise_ of it, is entirely frivolous, and that neither man nor any other being ought ever to be thought possessed of any ability, unless it be exerted and put in action. But though this be strictly true in a just and _philosophical_ way of thinking, 'tis certain it is not _the philosophy_ of our passions, but that many things operate upon them by means of the idea and supposition of power, independent of its actual exercise. We are pleased when we acquire an ability of procuring pleasure, and are displeased when another acquires a power of giving pain. This is evident from experience; but in order to give a just explication of the matter, and account for this satisfaction and uneasiness, we must weigh the following reflections. 'Tis evident the error of distinguishing power from its exercise proceeds not entirely from the scholastic doctrine of _free will_, which, indeed, enters very little into common life, and has but small influence on our vulgar and popular ways of thinking. According to that doctrine, motives deprive us not of free-will, nor take away our power of performing or forbearing any action. But according to common notions a man has no power, where very considerable motives lie betwixt him and the satisfaction of his desires, and determine him to forbear what he wishes to perform. I do not think I have fallen into my enemy's power when I see him pass me in the streets with a sword by his side, while I am, unprovided of any weapon. I know that the fear of the civil magistrate is as strong a restraint as any of iron, and that I am in as perfect safety as if he were chained or imprisoned. But when a person acquires such an authority over me, that not only there is no external obstacle to his actions, but also that he may punish or reward me as he pleases without any dread of punishment in his turn, I then attribute a full power to him, and consider myself as his subject or vassal.