The state of being cogent; the characteristic or quality of being reasonable and persuasive.(noun)
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Use "cogency" in a sentence
"Fforde's disregard for temporal paradox and cogency is uncommon but not unique."
"Arabic, on the other hand, the answer to the question, what is metrically long or short, is exceedingly simple, and flows with stringent cogency from the nature of the Arabic Alphabet."
"It fell in well enough with that love of emotional issues, that want of soberness and want of cogency, which is so characteristic of modern philosophers."