Propositions 41-47: Pleasure, hatred, fear

Proposition 41. Pleasure in itself is not bad but good: contrariwise, pain in itself is bad. Proof: Pleasure (3.11. and note) is emotion, whereby the body's power of activity is increased or helped; pain is emotion, whereby the body's power of activity is diminished or checked;   Proposition 42. Mirth cannot be excessive, but is always good; contrariwise, Melancholy is always bad. Proof: Mirth (see its Def. in 3.11. note) is pleasure, which, in so far as it is referred to the body, consists in all parts of the body being affected equally: that is (3.11.), the body's power of activity is increased or aided in such a manner, that the several parts maintain their former proportion of motion and rest;   Proposition 43. Stimulation may be excessive and bad; on the other hand, grief may be good, in so far as stimulation or pleasure is bad. Proof: Localized pleasure or stimulation (titillatio) is pleasure, which, in so far as it is referred to the body, consists in one or some of its parts being affected more than the rest (see its Definition 3.11. note).   Proposition 44. Love and desire may be excessive. Proof: Love is pleasure, accompanied by the idea of an external cause (Def. of Emotions, 6); Note: Mirth, which I have stated to be good, can be conceived more easily than it can be observed. Proposition 45. Hatred can never be good. Proof: When we hate a man, we endeavour to destroy him (3.39). Note: Here, and in what follows, I mean by hatred only hatred towards men. Corollary 1: Envy, derision, contempt, anger, revenge, and other emotions attributable to hatred, or arising therefrom, are bad.   Corollary 2: Whatsoever we desire from motives of hatred is base, and in a State unjust. Note: Between derision (which I have in Coroll. I. stated to be bad) and laughter I recognize a great difference.   Proposition 46. He, who lives under the guidance of reason, endeavours, as far as possible, to render back love, or kindness, for other men's hatred, anger, contempt, etc., towards him. Proof: All emotions of hatred are bad (4.45. Coroll. 1). Note: He who chooses to avenge wrongs with hatred is assuredly wretched.   Proposition 47. Emotions of hope and fear cannot be in themselves good. Proof: Emotions of hope and fear cannot exist without pain. Note: We may add, that these emotions show defective knowledge and an absence of power in the mind;