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;
Therefore (4.38) pleasure in itself is good, etc. Q.E.D.
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;
Therefore Mirth is always good (4.39), and cannot be excessive.
But Melancholy (see its Def. in the same note to 3.11) is pain, which, in so far as it is referred to the body, consists in the absolute decrease or hindrance of the body's power of activity; therefore (4.38) it is always bad. Q.E.D.
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).
The power of this emotion may be sufficient to overcome other actions of the body (4.6), and may remain obstinately fixed therein, thus rendering it incapable of being affected in a variety of other ways:
Therefore (4.38) it may be bad.
Again, grief, which is pain, cannot as such be good (4.41).
But, as its force and increase is defined by the power of an external cause compared with our own (4.5.), we can conceive infinite degrees and modes of strength in this emotion (4.3).
We can, therefore, conceive it as capable of restraining stimulation, and preventing its becoming excessive, and hindering the body's capabilities; thus, to this extent, it will be good. Q.E.D.
Proposition 44. Love and desire may be excessive. Proof: Love is pleasure, accompanied by the idea of an external cause (Def. of Emotions, 6);
Therefore stimulation, accompanied by the idea of an external cause is love (3.11. note).
Hence love maybe excessive.
Again, the strength of desire varies in proportion to the emotion from which it arises (3.37).
Now emotion may overcome all the rest of men's actions (4.6.).
So, therefore, can desire, which arises from the same emotion, overcome all other desires, and become excessive, as we showed in the last proposition concerning stimulation.
Note: Mirth, which I have stated to be good, can be conceived more easily than it can be observed.
For the emotions, whereby we are daily assailed, are generally referred to some part of the body which is affected more than the rest.
Hence the emotions are generally excessive, and so fix the mind in the contemplation of one object, that it is unable to think of others; and although men, as a rule, are a prey to many emotions—and very few are found who are always assailed by one and the same—yet there are cases, where one and the same emotion remains obstinately fixed.
We sometimes see men so absorbed in one object, that, although it be not present, they think they have it before them; when this is the case with a man who is not asleep, we say he is delirious or mad; nor are those persons who are inflamed with love, and who dream all night and all day about nothing but their mistress, or some woman, considered as less mad, for they are made objects of ridicule.
But when a miser thinks of nothing but gain or money, or when an ambitious man thinks of nothing but glory, they are not reckoned to be mad, because they are generally harmful, and are thought worthy of being hated.
But, in reality, Avarice, Ambition, Lust, &c., are species of madness, though they may not be reckoned among diseases.
Proposition 45. Hatred can never be good. Proof: When we hate a man, we endeavour to destroy him (3.39).
That is (4.37), we endeavour to do something that is bad.
Therefore, etc. Q.E.D.
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.
This is evident from 3.39. and 4.37.
Corollary 2: Whatsoever we desire from motives of hatred is base, and in a State unjust.
This also is evident from 3.39., and from the definitions of baseness and injustice in 4.37. note.
Note: Between derision (which I have in Coroll. I. stated to be bad) and laughter I recognize a great difference.
For laughter, as also jocularity, is merely pleasure; therefore, so long as it be not excessive, it is in itself good (4.41).
Assuredly nothing forbids man to enjoy himself, save grim and gloomy superstition.
For why is it more lawful to satiate one's hunger and thirst than to drive away one's melancholy?
I reason, and have convinced myself as follows:
No deity, nor anyone else, save the envious, takes pleasure in my infirmity and discomfort, nor sets down to my virtue the tears, sobs, fear, and the like, which axe signs of infirmity of spirit; on the contrary, the greater the pleasure wherewith we are affected, the greater the perfection whereto we pass; in other words, the more must we necessarily partake of the divine nature.
Therefore, to make use of what comes in our way, and to enjoy it as much as possible (not to the point of satiety, for that would not be enjoyment) is the part of a wise man.
I say it is the part of a wise man to refresh and recreate himself with moderate and pleasant food and drink, and also with perfumes, with the soft beauty of growing plants, with dress, with music, with many sports, with theatres, and the like, such as every man may make use of without injury to his neighbour.
For the human body is composed of very numerous parts, of diverse nature, which continually stand in need of fresh and varied nourishment, so that the whole body may be equally capable of performing all the actions, which follow from the necessity of its own nature;
and, consequently, so that the mind may also be equally capable of understanding many things simultaneously.
This way of life, then, agrees best with our principles, and also with general practice; therefore, if there be any question of another plan, the plan we have mentioned is the best, and in every way to be commended.
There is no need for me to set forth the matter more clearly or in more detail.
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).
Therefore he who lives under the guidance of reason will endeavour, as far as possible, to avoid being assailed by such emotions (4.19).
Consequently, he will also endeavour to prevent others being so assailed (4.37).
But hatred is increased by being reciprocated, and can be quenched by love (3.43), so that hatred may pass into love (3.44).
Therefore he who lives under the guidance of reason will endeavour to repay hatred with love, that is, with kindness. Q.E.D.
Note: He who chooses to avenge wrongs with hatred is assuredly wretched.
But he, who strives to conquer hatred with love, fights his battle in joy and confidence.
He withstands many as easily as one, and has very little need of fortune's aid.
Those whom he vanquishes yield joyfully, not through failure, but through increase in their powers;
all these consequences follow so plainly from the mere definitions of love and understanding, that I have no need to prove them in detail.
Proposition 47. Emotions of hope and fear cannot be in themselves good. Proof: Emotions of hope and fear cannot exist without pain.
For fear is pain (Def. of the Emotions, 13), and hope (Def. of the Emotions, Explanation 12 and 13) cannot exist without fear;
Therefore (4.41) these emotions cannot be good in themselves, but only in so far as they can restrain excessive pleasure (4.43). Q.E.D.
Note: We may add, that these emotions show defective knowledge and an absence of power in the mind;
for the same reason confidence, despair, joy, and disappointment are signs of a want of mental power.
For although confidence and joy are pleasurable emotions, they nevertheless imply a preceding pain, namely, hope and fear.
Wherefore the more we endeavour to be guided by reason, the less do we depend on hope; we endeavour to free ourselves from fear, and, as far as we can, to dominate fortune, directing our actions by the sure counsels of wisdom.