The influence of the relations of ideas (which we shall explain more fully afterwards) is plainly seen in this affair. In contrary passions, if the objects be totally different, the passions are like two opposite liquors in different bottles, which have no influence on each other. If the objects be intimately connected, the passions are like an alcali and an acid, which, being mingled, destroy each other. If the relation be more imperfect, and consist in the contradictory views of the same object, the passions are like oil and vinegar, which, however mingled, never perfectly unite and incorporate.