DL 6.53 · Diogenes
Noticing a good-looking youth lying in an exposed position, he nudged him and cried, "Up, man, up, lest some foe thrust a dart into thy back!" To one who was feasting lavishly he said: Short-liv'd thou'lt be, my son, by what thou – buy'st. As Plato was conversing about Ideas and using the nouns "tablehood" and "cuphood," he said, "Table and cup I see; but your tablehood and cuphood, Plato, I can nowise see." "That's readily accounted for," said Plato, "for you have the eyes to see the visible table and cup; but not the understanding by which ideal tablehood and cuphood are discerned."