In the suitableness or unsuitableness, in the proportion or disproportion which the affection seems to bear to the cause or object which excites it, consists the propriety or impropriety, the decency or ungracefulness of the consequent action. In the beneficial or hurtful nature of the effects which the affection aims at, or tends to produce, consists the merit or demerit of the action, the qualities by which it is entitled to reward, or is deserving of punishment. Philosophers have, of late years, considered chiefly the tendency of affections, and have given little attention to the relation which they stand in to the cause which excites them. In common life, however, when we judge of any person’s conduct, and of the sentiments which directed it, we constantly consider them under both these aspects. When we blame in another man the excesses of love, of grief, of resentment, we not only consider the ruinous effects which they tend to produce, but the little occasion which was given for them. The merit of his favourite, we say, is not so great, his misfortune is not so dreadful, his provocation is not so extraordinary, as to justify so violent a passion. We should have indulged, we say; perhaps, have approved of the violence of his emotion, had the cause been in any respect proportioned to it. When we judge in this manner of any affection, as proportioned or disproportioned to the cause which excites it, it is scarce possible that we should make use of any other rule or canon but the correspondent affection in ourselves. If, upon bringing the case home to our own breast, we find that the sentiments which it gives occasion to, coincide and tally with our own, we necessarily approve of them as proportioned and suitable to their objects; if otherwise, we necessarily disapprove of them, as extravagant and out of proportion. Every faculty in one man is the measure by which he judges of the like faculty in another. I judge of your sight by my sight, of your ear by my ear, of your reason by my reason, of your resentment by my resentment, of your love by my love. I neither have nor can have any other way of judging about them. CHAP. IV. _The same subject continued._ We may judge of the propriety or impropriety of the sentiments of another person by their correspondence or disagreement with our own, upon two different occasions; either, first, when the objects which excite them are considered without any peculiar relation, either to themselves or to the person whose sentiments we judge of; or, secondly, when they are considered as peculiarly affecting one or other of us.