by means of its double relations, the passion of hatred, instead of love, which, for the same reason, arises from virtue. To continue the experiment, I change anew the relation of ideas, and suppose the vice to belong to myself. What follows? What is usual. A subsequent change of the passion from hatred to humility. This humility I convert into pride by a new change of the impression; and find, after all, that I have completed the round, and have by these changes brought back the passion to that very situation in which I first found it. But to make the matter still more certain, I alter the object; and, instead of vice and virtue, make the trial upon beauty and deformity, riches and poverty, power and servitude. Each of these objects runs the circle of the passions in the same manner, by a change of their relations: and in whatever order we proceed, whether through pride, love, hatred, humility, or through humility, hatred, love, pride, the experiment is not in the least diversified. Esteem and contempt, indeed, arise on some occasions instead of love and hatred; but these are, at the bottom, the same passions, only diversified by some causes, which we shall explain afterwards. _Fifth experiment_. To give greater authority to these experiments, let us change the situation of affairs as much as possible, and place the passions and objects in all the different positions of which they are susceptible. Let us suppose, beside the relations above mentioned, that the person, along with whom I make all these experiments, is closely connected with me either by blood or friendship. He is, we shall suppose, my son or brother, or is united to me by a long and familiar acquaintance. Let us next suppose, that the cause of the passion acquires a double relation of impressions and ideas to this person; and let us see what the effects are of all these complicated attractions and relations. Before we consider what they are in fact, let us determine what they ought to be, conformable to my hypothesis. 'Tis plain, that, according as the impression is either pleasant or uneasy, the passion of love or hatred must arise towards the person who is thus connected to the cause of the impression by these double relations which I have all along required. The virtue of a brother must make me love him, as his vice or infamy must excite the contrary passion. But to judge only from the situation of affairs, I should not expect that the affections would rest there, and never transfuse themselves into any other impression. As there is here a person, who, by means of a double relation, is the object of my passion, the very same reasoning leads me to think the passion will be carried farther. The person has a relation of ideas to myself, according to the supposition; the passion of which he is the object, by being either agreeable or uneasy, has a relation of impressions to pride or humility. 'Tis evident, then, that one of these passions must arise from the love or hatred.