cogency vs validity

cogency and validity both are nouns.

Word	Noun	Adjective	Verb	Adverb
cogency	Yes	No	No	No
validity	Yes	No	No	No

As nouns, cogency and validity are synonyms defined as:

Other synonyms of cogency include rigor, rigour.

cogency (noun)	validity (noun)
the quality of being valid and rigorous	the quality of having legal force or effectiveness
persuasive relevance	the quality of being valid and rigorous