[468] The Blessed One said this: "Bhikkhus, there are these three characteristics of a fool, signs of a fool, and marks of a fool. What are the three? Here, bhikkhus, a fool is one who thinks bad thoughts, speaks bad speech, and does bad deeds. If, bhikkhus, a fool were not one who thinks bad thoughts, speaks bad speech, and does bad deeds, by what would the wise know of him: 'This worthy one is a fool, an untrue person (asappurisa)'? But since, bhikkhus, a fool is one who thinks bad thoughts, speaks bad speech, and does bad deeds, therefore the wise know of him: 'This worthy one is a fool, an untrue person.' That fool, bhikkhus, experiences threefold suffering (dukkha) and grief in this very life."
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.