| Suppose, then, that the object, concerning whose reality we are doubtful, is an object either of desire or aversion, it is evident, that, according as the mind turns itself either to the one side or the other, it must feel a momentary impression of joy or sorrow. |
| An object, whose existence we desire, gives satisfaction, when we reflect on those causes, which produce it; and for the same reason excites grief or uneasiness from the opposite consideration: So that as the understanding, in all probable questions, is divided betwixt the contrary points of view, the affections must in the same manner be divided betwixt opposite emotions. |
| Now if we consider the human mind, we shall find, that with regard to the passions, it is not the nature of a wind-instrument of music, which in running over all the notes immediately loses the sound after the breath ceases; but rather resembles a string-instrument, where after each stroke the vibrations still retain some sound, which gradually and insensibly decays. |
| The imagination is extreme quick and agile; but the passions are slow and restive: For which reason, when any object is presented, that affords a variety of views to the one, and emotions to the other; though the fancy may change its views with great celerity; each stroke will not produce a clear and distinct note of passion, but the one passion will always be mixt and confounded with the other. |
| According as the probability inclines to good or evil, the passion of joy or sorrow predominates in the composition: Because the nature of probability is to cast a superior number of views or chances on one side; or, which is the same thing, a superior number of returns of one passion; or since the dispersed passions are collected into one, a superior degree of that passion. |
| That is, in other words, the grief and joy being intermingled with each other, by means of the contrary views of the imagination, produce by their union the passions of hope and fear. |
| Upon this head there may be started a very curious question concerning that contrariety of passions, which is our present subject. |
| It is observable, that where the objects of contrary passions are presented at once, beside the encrease of the predominant passion (which has been already explained, and commonly arises at their first shock or rencounter) it sometimes happens, that both the passions exist successively, and by short intervals; sometimes, that they destroy each other, and neither of them takes place; and sometimes that both of them remain united in the mind. |
| It may, therefore, be asked, by what theory we can explain these variations, and to what general principle we can reduce them. |
| When the contrary passions arise from objects entirely different, they take place alternately, the want of relation in the ideas separating the impressions from each other, and preventing their opposition. |
| Thus when a man is afflicted for the loss of a law-suit, and joyful for the birth of a son, the mind running from the agreeable to the calamitous object, with whatever celerity it may perform this motion, can scarcely temper the one affection with the other, and remain betwixt them in a state of indifference. |
| It more easily attains that calm situation, when the same event is of a mixt nature, and contains something adverse and something prosperous in its different circumstances. |
| For in that case, both the passions, mingling with each other by means of the relation, become mutually destructive, and leave the mind in perfect tranquility. |
| But suppose, in the third place, that the object is not a compound of good or evil, but is considered as probable or improbable in any degree; in that case I assert, that the contrary passions will both of them be present at once in the soul, and instead of destroying and tempering each other, will subsist together, and produce a third impression or affection by their union. |
| Contrary passions are not capable of destroying each other, except when their contrary movements exactly rencounter, and are opposite in their direction, as well as in the sensation they produce. |
| This exact rencounter depends upon the relations of those ideas, from which they are derived, and is more or less perfect, according to the degrees of the relation. |
| In the case of probability the contrary chances are so far related, that they determine concerning the existence or non-existence of the same object. |
| But this relation is far from being perfect; since some of the chances lie on the side of existence, and others on that of non-existence; which are objects altogether incompatible. |
| It is impossible by one steady view to survey the opposite chances, and the events dependent on them; but it is necessary, that the imagination should run alternately from the one to the other. |
| Each view of the imagination produces its peculiar passion, which decays away by degrees, and is followed by a sensible vibration after the stroke. |
| The incompatibility of the views keeps the passions from shocking in a direct line, if that expression may be allowed; and yet their relation is sufficient to mingle their fainter emotions. |