If 'Only a man is a donkey' is necessarily false in all interpretations, any inference from it passes ST vacuously, which medieval logicians like John Buridan explicitly identified as a defect of purely substitutional accounts.
?Rate how convincing each reason is below to see the overall strength.
No one has weighed in yet. Be the first to share reasons for or against this statement.
Sign in or register to share your perspective on this statement.
interpretation(Formal semantics for modal nonmonotonic logic)
A complete, consistent set of literals
necessarily false(modal logic)
Something that cannot possibly be true under any circumstances—it's logically impossible, not just currently false.
passes vacuously(in formal logic)
A logical inference that technically 'works' according to the rules, but only because the starting point is impossible—like saying 'if pigs fly, then...' and calling any conclusion valid just because pigs never fly.
substitutional accounts(in philosophy of logic)
A theory in logic that says a statement is true or false based on whether you can swap in real things for the words without contradiction—in this case, trying to substitute something for 'man' and 'donkey'.