skilful debate; well-constructed argument
A classical expression referring to eloquent, persuasive speech reminiscent of the Warring States period rhetoricians Su Qin and Zhang Yi. Rare in modern Japanese; encountered mainly in literary or historical contexts.
His speech was truly a display of skilful debate.
From the names of the Chinese Warring States period diplomats Su Qin (蘇秦) and Zhang Yi (張儀), known for their persuasive rhetoric, combined with 弁 (speech, eloquence).