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.
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.