apothegm

mietelause A short, witty, instructive saying; an aphorism or maxim.
1665, w:Richard Head|Richard Head, The English Rogue: Deſcribed, in the Life of Merington Latroon, A Witty Extravagant, Being a Compleat Hiſtory of the Moſt Eminent Cheats of Both Sexes, Henry Marsh, http://books.google.com/books?id=Yv4BAAAAQAAJ&pg=PA355&dq=apothegm page 355,

Every glaſs of wine, or bit almoſt, that I committed to my mouth, ſhe uſhered thither with ſome Apothegm or other: the whole ſeries, indeed, of her diſcourſe, was compoſed of nothing but reaſon or wit, which made me admire her; which ſhe eaſily underſtood, I perceived by her ſmiles, when ſhe obſerved me gaping, as it were, when ſhe ſpoke, as if I would have eaten up her Words.

"You are too wonderful!" he would say. "How do you find time for everything?"

She rejoined with the apophthegm that made the rounds of Riseholme next day.

"My dear, it is just busy people that have time for everything."

For the gods have withheld from the barbarians the light of discretion, as that their poetry is not, like ours, full of choice apophthegms and useful maxims, but is all of love and war.

Which means roughly that business keeps one safe from love—ominous talk when one’s lover is a courtesan. I hoped that it was just another literary conceit I ought to know. (It is, I later learned, an apothegm by w:Ovid Ovid.)