One impression may be related to another, not only when their sensations are resembling, as we have all along supposed in the preceding cases; but also when their im pulses or directions are similar and correspondent.

This cannot take place with regard to pride and humility; because these are only pure sensations, without any direction or tendency to action.

We are, therefore, to look for instances of this peculiar relation of impressions only in such affections, as are attended with a certain appetite or desire; such as those of love and hatred.
Benevolence or the appetite, which attends love, is a desire of the happiness of the person beloved, and an aversion to his misery; as anger or the appetite, which attends hatred, is a desire of the misery of the person hated, and an aversion to his happiness.

A desire, therefore, of the happiness of another, and aversion to his misery, are similar to benevolence; and a desire of his misery and aversion to his happiness are correspondent to anger.

Now pity is a desire of happiness to another, and aversion to his misery; as malice is the contrary appetite.
Pity, then, is related to benevolence; and malice to anger: And as benevolence has been already found to be connected with love, by a natural and original quality, and anger with hatred; it is by this chain the passions of pity and malice are connected with love and hatred.
This hypothesis is founded on sufficient experience.