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Triviality
Cogito ergo sum Logic and rhetoric |
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Key articles |
General logic |
Bad logic |
Triviality is a property of formal systems in logic. A system is trivial if its set of axioms entails every well-formed formula according to the inference rules of the system, i.e.,
An example of triviality is a classical propositional system containing contradictory sentences for axioms; in such a system the principle of explosion can be used to infer any possible proposition or sentence.
On the other hand, a system of paraconsistent logic can be non-trivial even if it contains contradictory axioms, since its inference rules do not include the principle of explosion.