Love is joy with the accompanying idea of an external cause. Pleasurable excitement, therefore with the accompanying idea of an external cause, is love, and therefore love may be excessive. Again, desire is greater as the emotion from which it springs is greater. Inasmuch, therefore, as an emotion may overpower the other actions of a man, so also the desire which springs from this emotion may also overpower the other desires, and may therefore exist in the same excess which we have shown (in the preceding proposition) that pleasurable excitement possesses.
Cheerfulness, which I have affirmed to be good, is more easily imagined than observed; for the emotions by which we are daily agitated are generally related to some part of the body which is affected more than the others, and therefore it is that the emotions exist for the most part in excess, and so hold the mind down to the contemplation of one object alone, that it can think about nothing else; and although men are subject to a number of emotions, and therefore few are found who are always under the control of one and the same emotion, there are not wanting those to whom one and the same emotion obstinately clings. We see men sometimes so affected by one object, that although it is not present, they believe it to be before them; and if this happens to a man who is not asleep, we say that he is delirious or mad. Nor are those believed to be less mad who are inflamed by love, dreaming about nothing but a mistress or harlot day and night, for they excite our laughter. But the avaricious man who thinks of nothing else but gain or money, and the ambitious man who thinks of nothing but glory, inasmuch as they do harm, and are, therefore, thought worthy of hatred, are not believed to be mad. In truth, however, avarice, lust, etc., are a kind of madness, although they are not reckoned amongst diseases.
IV
The Evil Emotions
The man whom we hate we endeavor to destroy, that is to say we endeavor to do something which is evil. Therefore hatred can never be good.[31]
Envy, mockery, contempt, anger, revenge, and the other affects which are related to hatred or arise from it, are evil.
Everything which we desire because we are affected by hatred is base and unjust in the State.
I make a great distinction between mockery (which I have said is bad) and laughter; for laughter and merriment are nothing but joy, and therefore, provided they are not excessive, are in themselves good. Nothing but a gloomy and sad superstition forbids enjoyment. For why is it more seemly to extinguish hunger and thirst than to drive away melancholy? My reasons and my conclusions are these: No God and no human being, except an envious one, is delighted by my impotence or my trouble, or esteems as any virtue in us tears, sighs, fears, and other things of this kind, which are signs of mental impotence; on the contrary, the greater the joy with which we are affected, the greater the perfection to which we pass thereby, that is to say, the more do we necessarily partake of the divine nature. To make use of things, therefore, and to delight in them as much as possible (provided we do not disgust ourselves with them, which is not delighting in them), is the part of a wise man. It is the part of a wise man, I say, to refresh and invigorate himself with moderate and pleasant eating and drinking, with sweet scents and the beauty of green plants, with ornament, with music, with sports, with the theater, and with all things of this kind which one man can enjoy without hurting another. For the human body is composed of a great number of parts of diverse nature, which constantly need new and varied nourishment, in order that the whole of the body may be equally fit for everything which can follow from its nature, and consequently that the mind may be equally fit to understand many things at once. This mode of living best of all agrees both with our principles and with common practice; therefore this mode of living is the best of all, and is to be universally commended. There is no need, therefore, to enter more at length into the subject.
All emotions of hatred are evil and therefore the man who lives according to the guidance of reason will strive as much as possible to keep himself from being agitated by the emotions of hatred and, consequently, will strive to keep others from being subject to the same emotions. But hatred is increased by reciprocal hatred, and, on the other hand, can be extinguished by love, so that hatred passes into love. Therefore he who lives according to the guidance of reason will strive to repay the hatred of another, etc., with love, that is to say, with generosity. He who wishes to avenge injuries by hating in return does indeed live miserably. But he who, on the contrary, strives to drive out hatred by love, fights joyfully and confidently, with equal ease resisting one man or a number of men, and needing scarcely any assistance from fortune. Those whom he conquers yield gladly, not from defect of strength, but from an increase of it. These truths, however, all follow so plainly from the definitions alone of love and the intellect, that there is no need to demonstrate them singly.