A small object makes a great one appear still greater.
A great object makes a little one appear less.

Deformity of itself produces uneasiness; but makes us receive new pleasure by its contrast with a beautiful object, whose beauty is augmented by it; as on the other hand, beauty, which of itself produces pleasure, makes us receive a new pain by the contrast with any thing ugly, whose deformity it augments.

The case, therefore, must be the same with happiness and misery.

The direct survey of another's pleasure naturally gives us plcasure, and therefore produces pain when cornpared with our own.

His pain, considered in itself, is painful to us, but augments the idea of our own happiness, and gives us pleasure.
Nor will it appear strange, that we may feel a reverst sensation from the happiness and misery of others; since we find the same comparison may give us a kind of malice against ourselves, and make us rejoice for our pains, and grieve for our pleasures.