<logic> A finite, non-empty sequence of wffs in which the last member is the wff derived, and each of the others (the premises) is either an axiom, a member of a set of accepted premises, or the result of applying a rule of inference to wffs preceding it in the sequence.
Notation: Gamma |- A (the wff A can be derived from the set of wffs G ).
See corresponding argument, proof
[Glossary of First-Order Logic]
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