Jealousy may be defined as a painful emotion on noticing, or imagining, that some one dear to us loves another more than us. Unlike affection in general, and like sympathy, it therefore necessarily refers to a sentient being and a possible reciprocation of affection. It is a form of rivalry, of which there are two kinds: rivalry for the possession of an object or a position; and rivalry for the first place in a person’s affections. The first is not incompatible with friendship, for two rival candidates for a political office or a college fellowship are not necessarily personal enemies. But the second kind, which, when allied with doubt is called Jealousy, is a deadly enemy of good-will; and there is probably no cause that has broken so many friendships as the “green-eyed monster,” among women no less than among men. Modern psychology agrees with St. Augustine that “he that is not jealous, is not in love.” There can be no love without Jealousy—potential at any rate, for in the absence of provocation it may perhaps never manifest itself. But there can be Jealousy without love, _i.e_ without sexual love; for that passion is often aroused in connection with other kinds of affection—parental, filial, etc. Stories are told of dogs practically committing suicide by disappearing or pining away if displaced by a younger pet in the affection of a family; and those who have seen specimens of canine jealousy find nothing improbable in these stories. Yet as a rule all these general forms of jealousy—as when a husband is jealous of his wife if the children show her special favour, or as when a mother is jealous of a visitor loved by her children—are mere trifles compared with sexual Jealousy, romantic and conjugal. It is in painting this form of Jealousy that poets have exhausted the strength of language. “Of all the passions in the mind thou vilest art,” says Spenser of this “king of torments,” “the injured lover’s hell.” With this, when once the lover’s mind is affected— “’Tis then delightful misery no more, But agony unmixt, incessant gall.” “But, O, what damnéd minutes tells he o’er Who dotes, yet doubts, suspects, yet strongly loves.”