The sestet applies the emetical trope to love: a "policy" is a course of prudent action. Love, to be prudent and to forestall future ailings ("to anticipate / The ills that were, not"), acquainted itself early with transgressions ("grew to faults assured") that operate like a curative vomit. In so doing, love submitted to medicine ("brought to medicine") "a healthful state", a state reeking of goodness ("rank of goodness"). The "healthful state", with its goodness, "would by ill be cured", would as if by an initial, induced sickness be cured. The moral the poet has learnt and has proved by bitter experience is that potions ("Drugs", in this case transgressions), rather than acting as an antidote to the disease of love, only act to poison love.