List of 426 Sets of Synonyms - How they Differ - Total of 2307 Words - 412

SYNONYMS: valid, sound, cogent, convincing, telling.
These adjectives describe assertions, arguments, conclusions, reasons, or intellectual processes that are persuasive because they are well founded, as in fact, logic, or rationality.

What is valid is based on or borne out by truth or fact or has legal force: a valid excuse; a valid claim.
What is sound is free from logical flaws or is based on valid reasoning: a sound theory; sound principles.
Something cogent is both sound and compelling: cogent testimony; a cogent explanation.
Convincing implies the power to dispel doubt or overcome resistance or opposition: convincing proof.
Telling means strikingly effective: The attorney's summation was telling.