Kathavatthusutta 4.2

4.2

Sacāyaṃ, bhikkhave, puggalo pañhaṃ puṭṭho samāno aññenaññaṃ paṭicarati, bahiddhā kathaṃ apanāmeti, kopañca dosañca appaccayañca pātukaroti, evaṃ santāyaṃ, bhikkhave, puggalo akaccho hoti.

When an individual is asked a question, if they dodge the issue; distract the discussion with irrelevant points; or display annoyance, hate, and bitterness, then that individual is not competent to hold a discussion.