Finitary arithmetic is a mathematical approach that emphasizes constructive methods, avoiding infinite concepts. It focuses on operations and proofs that…
Exportation is a logical principle that rewrites (P AND Q) -> R as P -> (Q -> R). It effectively…
A rule of inference in logic that allows the introduction of an existential quantifier (∃). It asserts the existence of…
The principle of double negation introduction states that for any proposition P, P implies the double negation of P (¬¬P).…
The disjunction property in intuitionistic logic asserts that if a statement P or Q is provable, then either P alone…
Discharge is the act of eliminating an assumption within a logical derivation. It's a crucial step, often used to prove…
A derivable rule is a logical rule that can be derived from the existing axioms and inference rules of a…
Deductive validity ensures that if premises are true, the conclusion *must* be true. It's a cornerstone of logical reasoning, guaranteeing…
The deduction theorem states that if a statement can be derived from a set of premises plus an additional statement,…
A fundamental procedure in proof theory that systematically removes 'cuts' from a proof. This process simplifies proofs and demonstrates that…