<logic, epistemology> "to the stronger," or "even more so. " We are bound to accept an a fortiori claim because of our prior acceptance of a weaker application of the same reasoning or truth. Thus, for example: Frank can't run to the store in less than five minutes, and the restaurant is several blocks further away than the store. Thus, a fortiori, Frank can't run to the restaurant in less than five minutes.
[A Dictionary of Philosophical Terms and Names]
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