[339] Then a certain bhikkhu approached another bhikkhu and, having approached, said to that bhikkhu: "In what way, friend, is a bhikkhu's vision (dassana) well purified?"
"Friend, when a bhikkhu understands as it really is (yathābhūta) the origin and the passing away of the six bases for contact (phassāyatana), to that extent, friend, a bhikkhu's vision is well purified."
Then that bhikkhu, dissatisfied with that bhikkhu's answer to the question, approached another bhikkhu and, having approached, said to that bhikkhu: "In what way, friend, is a bhikkhu's vision well purified?"
"Friend, when a bhikkhu understands as it really is the origin and the passing away of the five aggregates subject to clinging (upādānakkhandha), to that extent, friend, a bhikkhu's vision is well purified."
Then that bhikkhu, dissatisfied with that bhikkhu's answer to the question, approached another bhikkhu and, having approached, said to that bhikkhu: "In what way, friend, is a bhikkhu's vision well purified?"
"Friend, when a bhikkhu understands as it really is the origin and the passing away of the four great elements (mahābhūta), to that extent, friend, a bhikkhu's vision is well purified."
Then that bhikkhu, dissatisfied with that bhikkhu's answer to the question, approached another bhikkhu and, having approached, said to that bhikkhu: "In what way, friend, is a bhikkhu's vision well purified?"
"Friend, when a bhikkhu understands as it really is: 'Whatever is subject to origination, all that is subject to cessation,' to that extent, friend, a bhikkhu's vision is well purified."
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.