What is A FORTIORI? Definition of A FORTIORI in Black's Law Dictionary
With stronger reason; much more. A term used in logic to denote an argument to the effect that because one ascertained fact exists, therefore another, which is included in it, or analogous to it, and which is less improbable, unusual, or surprising, must also exist.
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That's the definition of A FORTIORI in Black's Law Dictionary - Courtesy of Cekhukum.com.