Argumentum a fortiori
Argumentum a fortiori (literally "argument from the stronger [reason]") (UK: , US: ) is a form of argumentation that draws upon existing confidence in a proposition to argue in favour of a second proposition that is held to be implicit in, or even more certain than, the first. == Usage == === American usage === In Garner's Modern American Usage, Garner says writers sometimes use a fortiori as an adjective, although he writes it is "a usage to be resisted".