Thus, there are necessarily as many kinds of pleasure, pain, love, hatred, &c., as there are kinds of objects whereby we are affected. Now desire is each man's essence or nature, in so far as it is conceived as determined to a particular action by any given modification of itself (III. ix. note); therefore, according as a man is affected through external causes by this or that kind of pleasure, pain, love, hatred, &c., in other words, according as his nature is disposed in this or that manner, so will his desire be of one kind or another, and the nature of one desire must necessarily differ from the nature of another desire, as widely as the emotions differ, wherefrom each desire arose. Thus there are as many kinds of desire, as there are kinds of pleasure, pain, love, &c., consequently (by what has been shown) there are as many kinds of desire, as there are kinds of objects whereby we are affected. Q.E.D. *****Note--Among the kinds of emotions, which, by the last proposition, must be very numerous, the chief are "luxury," "drunkenness," "lust," "avarice," and "ambition," being merely species of love or desire, displaying the nature of those emotions in a manner varying according to the object, with which they are concerned. For by luxury, drunkenness, lust, avarice, ambition, &c., we simply mean the immoderate love of feasting, drinking, venery, riches, and fame. Furthermore, these emotions, in so far as we distinguish them from others merely by the objects wherewith they are concerned, have no contraries. For "temperance," "sobriety," and "chastity," which we are wont to oppose to luxury, drunkenness, and lust, are not emotions or passive states, but indicate a power of the mind which moderates the last-named emotions. However, I cannot here explain the remaining kinds of emotions (seeing that they are as numerous as the kinds of objects), nor, if I could, would it be necessary. It is sufficient for our purpose, namely, to determine the strength of the emotions, and the mind's power over them, to have a general definition of each emotion. It is sufficient, I repeat, to understand the general properties of the emotions and the mind, to enable us to determine the quality and extent of the mind's power in moderating and checking the emotions. Thus, though there is a great difference between various emotions of love, hatred, or desire, for instance between love felt towards children, and love felt towards a wife, there is no need for us to take cognizance of such differences, or to track out further the nature and origin of the emotions. 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.