In other words, he will endeavour not to hate him (III.
xli.), and not to affect him painfully; this endeavour (III.
xxxvii.) will be greater or less in proportion to the emotion from which it arises.

Therefore, if it be greater than that which arises from hatred, and through which the man endeavours to affect painfully the thing which he hates, it will get the better of it and banish the hatred from his mind.

Q.E.D.
PROP.XLIV.

Hatred which is completely vanquished by love passes into love: and love is thereupon greater than if hatred had not preceded it.
Proof .-- The proof proceeds in the same way as Prop.

xxxviii.
of this Part: for he who begins to love a thing, which he was wont to hate or regard with pain, from the very fact of loving feels pleasure.