In a manner employing the logical method of apagoge; by proving through contradiction or reduction to absurdity.
From 'apagogical' + the suffix '-ally,' converting the adjective into an adverb describing how something is argued or proven.
When you hear someone say 'Let me argue this apagogically,' you know they're about to be clever and a bit show-offy—which is fair, because it's a genuinely sophisticated technique.
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