A FORTIORI

(L. “from a stronger [reason]’); the term used for an argument, which justifies an assertion by a reference to a proved conclusion, which is included in the assertion. It can be depicted thus: if a statement A is proved less than B, and is understood to be greater than C, it follows a fortiori that C is less than B without further proof. The argument is frequently based merely on a comparison of probabilities, when it constitutes an appeal to common reasoning. E.g. 1. “But if God so clothes the grass of the field, which today is alive and tomorrow is thrown into the oven, will he not much more clothe you, O men of little faith?’ (Mt 6:30); 2. All the citizens are to abide by the law of his State. The president of the State being its first citizen should abide by the law.