The Compendium of Caraka 3.8.17

3.8.17

tatra jñānavijñānavacanaprativacanaśaktisaṃpannenākopanenānupaskṛtavidyenānasūyakenānuneyenānunayakovidena kleśakṣameṇa priyasaṃbhāṣaṇena ca saha sandhāyasaṃbhāṣā vidhīyate/

Among them, friendly discussion is prescribed with one endowed with knowledge, specialized understanding, and the power of statement and rejoinder, free from anger, possessing uncorrupted knowledge, unmalicious, amenable to reason, skilled in reasoning, capable of enduring hardship, and speaking pleasantly.