PROP. LVII. Any emotion of a given individual differs from the emotion of another individual, only in so far as the essence of the one individual differs from the essence of the other.
Proof.—This proposition is evident from Ax. i. (which see after Lemma iii. Prop. xiii., Part II.). Nevertheless, we will prove it from the nature of the three primary emotions.
All emotions are attributable to desire, pleasure, or pain, as their Definitions above given show. But desire is each man’s nature or essence (III. ix. note); therefore desire in one individual differs from desire in another individual, only in so far as the nature or essence of the one differs from the nature or essence of the other. Again, pleasure and pain are passive states or passions, whereby every man’s power or endeavour to persist in his being is increased or diminished, helped or hindered (III. xi. and note). But by the endeavour to persist in its being, in so far as it is attributable to mind and body in conjunction, we mean appetite and desire (III. ix. note); therefore pleasure and pain are identical with desire or appetite, in so far as by external causes they are increased or diminished, helped or hindered, in other words, they are every man’s nature; wherefore the pleasure and pain felt by one man differ from the pleasure and pain felt by another man, only in so far as the nature or essence of the one man differs from the essence of the other; consequently, any emotion of one individual only differs, &c. Q.E.D.
Note.—Hence it follows, that the emotions of the animals which are called irrational (for after learning the origin of mind we cannot doubt that brutes feel) only differ from man’s emotions, to the extent that brute nature differs from human nature. Horse and man are alike carried away by the desire of procreation; but the desire of the former is equine, the desire of the latter is human. So also the lusts and appetites of insects, fishes, and birds must needs vary according to the several natures. Thus, although each individual lives content and rejoices in that nature belonging to him wherein he has his being, yet the life, wherein each is content and rejoices, is nothing else but the idea, or soul, of the said individual, and hence the joy of one only differs in nature from the joy of another, to the extent that the essence of one differs from the essence of another. Lastly, it follows from the foregoing proposition, that there is no small difference between the joy which actuates, say, a drunkard, and the joy possessed by a philosopher, as I just mention here by the way. Thus far I have treated of the emotions attributable to man, in so far as he is passive. It remains to add a few words on those attributable to him in so far as he is active.
PROP. LVIII. Besides pleasure and desire, which are passivities or passions, there are other emotions derived from pleasure and desire, which are attributable to us in so far as we are active.
Proof.—When the mind conceives itself and its power of activity, it feels pleasure (III. liii.): now the mind necessarily contemplates itself, when it conceives a true or adequate idea (II. xliii.). But the mind does conceive certain adequate ideas (II. xl. note 2.). Therefore it feels pleasure in so far as it conceives adequate ideas; that is, in so far as it is active (III. i.). Again, the mind, both in so far as it has clear and distinct ideas, and in so far as it has confused ideas, endeavours to persist in its own being (III. ix.); but by such an endeavour we mean desire (by the note to the same Prop.); therefore, desire is also attributable to us, in so far as we understand, or (III. i.) in so far as we are active. Q.E.D.
PROP. LIX. Among all the emotions attributable to the mind as active, there are none which cannot be referred to pleasure or desire.
Proof.—All emotions can be referred to desire, pleasure, or pain, as their Definitions, already given, show. Now by pain we mean that the mind’s power of thinking is diminished or checked (III. xi. and note); therefore, in so far as the mind feels pain, its power of understanding, that is, of activity, is diminished or checked (III. i.); therefore, no painful emotions can be attributed to the mind in virtue of its being active, but only emotions of pleasure and desire, which (by the last Prop.) are attributable to the mind in that condition. Q.E.D.
Note.—All actions following from emotion, which are attributable to the mind in virtue of its understanding, I set down to strength of character (fortitudo), which I divide into courage (animositas) and highmindedness (generositas). By courage I mean the desire whereby every man strives to preserve his own being in accordance solely with the dictates of reason. By highmindedness I mean the desire whereby every man endeavours, solely under the dictates of reason, to aid other men and to unite them to himself in friendship. Those actions, therefore, which have regard solely to the good of the agent I set down to courage, those which aim at the good of others I set down to highmindedness. Thus temperance, sobriety, and presence of mind in danger, &c., are varieties of courage; courtesy, mercy, &c., are varieties of highmindedness.
I think I have thus explained, and displayed through their primary causes the principal emotions and vacillations of spirit, which arise from the combination of the three primary emotions, to wit, desire, pleasure, and pain. It is evident from what I have said, that we are in many ways driven about by external causes, and that like waves of the sea driven by contrary winds we toss to and fro unwitting of the issue and of our fate. But I have said, that I have only set forth the chief conflicting emotions, not all that might be given. For, by proceeding in the same way as above, we can easily show that love is united to repentance, scorn, shame, &c. I think everyone will agree from what has been said, that the emotions may be compounded one with another in so many ways, and so many variations may arise therefrom, as to exceed all possibility of computation. However, for my purpose, it is enough to have enumerated the most important; to reckon up the rest which I have omitted would be more curious than profitable. It remains to remark concerning love, that it very often happens that while we are enjoying a thing which we longed for, the body, from the act of enjoyment, acquires a new disposition, whereby it is determined in another way, other images of things are aroused in it, and the mind begins to conceive and desire something fresh.
For example, when we conceive something which generally delights us with its flavour, we desire to enjoy, that is, to eat it. But whilst we are thus enjoying it, the stomach is filled and the body is otherwise disposed. If, therefore, when the body is thus otherwise disposed, the image of the food which is present be stimulated, and consequently the endeavour or desire to eat it be stimulated also, the new disposition of the body will feel repugnance to the desire or attempt, and consequently the presence of the food which we formerly longed for will become odious. This revulsion of feeling is called satiety or weariness. For the rest, I have neglected the outward modifications of the body observable in emotions, such, for instance, as trembling, pallor, sobbing, laughter, &c., for these are attributable to the body only, without any reference to the mind. Lastly, the Definitions of the emotions require to be supplemented in a few points; I will therefore repeat them, interpolating such observations as I think should here and there be added.
Definitions Of The Emotions
I. Desire is the actual essence of man, in so far as it is conceived, as determined to a particular activity by some given modification of itself.
Explanation.—We have said above, in the note to Prop. ix. of this part, that desire is appetite, with consciousness thereof; further, that appetite is the essence of man, in so far as it is determined to act in a way tending to promote its own persistence. But, in the same note, I also remarked that, strictly speaking, I recognize no distinction between appetite and desire. For whether a man be conscious of his appetite or not, it remains one and the same appetite. Thus, in order to avoid the appearance of tautology, I have refrained from explaining desire by appetite; but I have take care to define it in such a manner, as to comprehend, under one head, all those endeavours of human nature, which we distinguish by the terms appetite, will, desire, or impulse. I might, indeed, have said, that desire is the essence of man, in so far as it is conceived as determined to a particular activity; but from such a definition (cf. II. xxiii.) it would not follow that the mind can be conscious of its desire or appetite. Therefore, in order to imply the cause of such consciousness, it was necessary to add, in so far as it is determined by some given modification, &c. For,
