3. _Love_ is a generic passion, having for its species _desire_ and
_delight_, the contraries of which are _abhorrence_ and _pain_. Desire
is of absent good; abhorrence is of absent evil; delight is in present
good; pain is at present evil. The good and the evil which is the
object of any passion must be apprehended by sense, or by imagination
in a sensible way, whether itself be a thing of sense or not.

4. Desire and abhorrence, delight and pain, are conversant with good
and evil simply. But good is often attainable only by an effort, and
evil avoidable by an effort. The effort that good costs to attain
casts a shade of evil or undesirableness over it: we may shrink from
the effort while coveting the good. Again, the fact of evil being at
all avoidable is a good thing about such evil. If we call evil black,
and good white, avoidable evil will be black just silvering into grey:
and arduous good will be white with a cloud on it. And if the white
attracts, and the black repels the appetite, it appears that arduous
good is somewhat distasteful, to wit, to the faint-hearted; and
avoidable, or vincible, evil has its attraction for the man of spirit.
About these two objects, good hard of getting and evil hard of
avoidance, arise four other passions, hope and despair about the
former, fear and daring about the latter. Hope goes out towards a
difficult good: despair flies from it, the difficulty here being more
repellent than the good is attractive. Fear flies from a threatening
evil: while daring goes up to the same, drawn by the likelihood of
vanquishing it. _Desire_ and _abhorrence_, _delight_ and _pain_, hope
and despair, fear and daring, with anger and hatred (of which
presently), complete our list of passions.

5. Aristotle and his school of old, called Peripatetics, recommended