<logic, philosophy of science> the most crucial distinction among deductive arguments and the inferences upon which they rely. In a valid argument, if the premises are true, then the conclusion must also be true. Alternatively: it is impossible for the premises of a valid argument to be true while its conclusion is false. All other arguments are invalid; that is, it is possible for their conclusions to be false even when their premises are true. Thus, even the most reliable instances of inductive reasoning fall short of deductive validity. Recommended Reading: Graham Priest, Logic: A Very Short Introduction (Oxford, 2000) and Patrick Suppes, Introduction to Logic (Dover, 1999).
[A Dictionary of Philosophical Terms and Names]
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