Ethics · Benedictus de Spinoza
GENERAL DEFINITION OF THE EMOTIONS
Emotion, which is called a passivity of the soul, is a confused idea, whereby the mind affirms concerning its body, or any part thereof, a force for existence (existendi vis) greater or less than before, and by the presence of which the mind is determined to think of one thing rather than another. Explanation--I say, first, that emotion or passion of the soul is a confused idea. For we have shown that the mind is only passive, in so far as it has inadequate or confused ideas. (III. iii.) I say, further, whereby the mind affirms concerning its body or any part thereof a force for existence greater than before. For all the ideas of bodies, which we possess, denote rather the actual disposition of our own body (II. xvi. Coroll. ii.) than the nature of an external body. But the idea which constitutes the reality of an emotion must denote or express the disposition of the body, or of some part thereof, because its power of action or force for existence is increased or diminished, helped or hindered. But it must be noted that, when I say a greater or less force for existence than before, I do not mean that the mind compares the present with the past disposition of the body, but that the idea which constitutes the reality of an emotion affirms something of the body, which, in fact, involves more or less of reality than before.
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