Then a certain bhikkhu approached the Blessed One … and said to him: “Venerable sir, is there one thing through the abandoning of which ignorance is abandoned by a bhikkhu and true knowledge arises?”

“There is one thing, bhikkhu, through the abandoning of which ignorance is abandoned by a bhikkhu and true knowledge arises.”

“And what is that one thing, venerable sir?”

“Ignorance, bhikkhu, is that one thing through the abandoning of which ignorance is abandoned by a bhikkhu and true knowledge arises.”

“But, venerable sir, how should a bhikkhu know, how should he see, for ignorance to be abandoned by him and true knowledge to arise?”

“Bhikkhu, when a bhikkhu knows and sees the eye as impermanent, ignorance is abandoned by him and true knowledge arises. When he knows and sees forms as impermanent … When he knows and sees as impermanent whatever feeling arises with mind-contact as condition … ignorance is abandoned by him and true knowledge arises.

“When, bhikkhu, a bhikkhu knows and sees thus, ignorance is abandoned by him and true knowledge arises.”