Thus I have heard: The Buddha was staying at the Kalandaka Bamboo Grove of Rājagṛha. At the time, Venerable Śāriputra and Venerable Mahākauṣṭhila were on Mount Gṛdhrakūṭa.
Venerable Kauṣṭhila rose from meditation in the afternoon and visited Śāriputra. Once they had exchanged greetings and joked in various ways, he withdrew to sit to one side.
Venerable Mahākauṣṭhila said to Śāriputra, “I have a question I’d like to ask if you might have some time to explain it for me?”
Śāriputra said, “Go ahead with your question, sir. I will tell you what I know.”
Venerable Mahākauṣṭhila said to Śāriputra, “There’s the term ‘ignorance.’ What is ignorance? Who possesses this ignorance?”
Śāriputra replied, “Ignorance means to not know. Someone who doesn’t know is ignorant.”
“What is it that they don’t know?”
“It’s that form is impermanent. They truly don’t know that form is impermanent. Form is something that erodes. They truly don’t know that form is something that erodes. Form is something that arises and ceases. They truly don’t know that form is something that arises and ceases. Feeling … conception … volition … awareness [is impermanent.] They truly don’t know that awareness is impermanent. Awareness is something that erodes. They truly don’t know that awareness is something that erodes. Awareness is something that arises and ceases. They truly don’t know that awareness is something that arises and ceases. Mahākauṣṭhila, they truly don’t know these five acquired aggregates. They don’t see and have no direct realization of them. They are foolish, benighted, and aren’t insightful. This is called ignorance. Someone who achieves this is called ignorant.”
Mahākauṣṭhila asked, “Śāriputra, there’s that term ‘insight.’ What is insight? Who possesses this insight?”
Śāriputra said, “Mahākauṣṭhila, the term insight means to know. Someone who knows is called insightful.”
Mahākauṣṭhila asked, “What is it that they know?”
“It’s that form is impermanent. They truly know that form is impermanent. Form is something that erodes. They truly know that form is something that erodes. Form is something that arises and ceases. They truly know that form is something that arises and ceases. Feeling … conception … volition … awareness [is impermanent.] They truly know that awareness is impermanent. Awareness is something that erodes. They truly know that awareness is something that erodes. Awareness is something that arises and ceases. They truly know that awareness is something that arises and ceases. Kauṣṭhila, they truly know these five acquired aggregates. They see and have insight about them. They are aware, wise, and directly realize it. This is called insight. Someone who achieves this is called insightful.”
Those two proper gentlemen each heard that teaching and were in turn delighted by it. They rose from their seats, and each returned to his home.