Kathāvatthusuttaṃ [AN 3.67, PTS 1.198–1.199]

7.

The Discourse on Points of Controversy

68. "There are, monks, these three topics of discussion. What three? One might discuss referring to the past period of time - 'Thus it was in the past period of time.' Or one might discuss referring to the future period of time - 'Thus it will be in the future period of time.' Or one might discuss referring to the present period of time now - 'Thus it is in the present period of time now.'"

"By association with discussion, monks, a person should be known as to whether he is fit for discussion or not fit for discussion. If, monks, this person when asked a question does not answer definitively a question requiring a definitive answer, does not answer analytically a question requiring an analytical answer, does not answer with a counter-question a question requiring a counter-question, does not set aside a question requiring to be set aside, this being so, monks, this person is not fit for discussion. But if, monks, this person when asked a question answers definitively a question requiring a definitive answer, answers analytically a question requiring an analytical answer, answers with a counter-question a question requiring a counter-question, sets aside a question requiring to be set aside, this being so, monks, this person is fit for discussion.

"By association with discussion, monks, a person should be known as to whether he is fit for discussion or not fit for discussion. If, monks, this person when asked a question does not stand firm on the possible and impossible, does not stand firm on the supposition, does not stand firm on the acknowledged doctrine, does not stand firm on the practice, this being so, monks, this person is not fit for discussion. But if, monks, this person when asked a question stands firm on the possible and impossible, stands firm on the supposition, stands firm on the acknowledged doctrine, stands firm on the practice, this being so, monks, this person is fit for discussion.

"By association with discussion, monks, a person should be known as to whether he is fit for discussion or not fit for discussion. If, monks, this person when asked a question evades the issue with another issue, diverts the discussion outside, and manifests irritation, hate, and displeasure, this being so, monks, this person is not fit for discussion. But if, monks, this person when asked a question does not evade the issue with another issue, does not divert the discussion outside, and does not manifest irritation, hate, and displeasure, this being so, monks, this person is fit for discussion.

"By association with discussion, monks, a person should be known as to whether he is fit for discussion or not fit for discussion. If, monks, this person when asked a question overwhelms, crushes, laughs derisively, and seizes upon slips, this being so, monks, this person is not fit for discussion. But if, monks, this person when asked a question does not overwhelm, does not crush, does not laugh derisively, and does not seize upon slips, this being so, monks, this person is fit for discussion.

"By association with discussion, monks, a person should be known as to whether he has the proximate cause or is without the proximate cause. One who does not incline the ear, monks, is without the proximate cause; one who inclines the ear has the proximate cause. He, having the proximate cause, directly knows one thing, fully understands one thing, abandons one thing, realises one thing. He, directly knowing one thing, fully understanding one thing, abandoning one thing, realising one thing, touches right liberation. For this purpose, monks, is discussion; for this purpose is consultation; for this purpose is the proximate cause; for this purpose is the giving ear, that is to say, the deliverance of the mind through non-clinging."