is a substitution instance of: P & Q and (A ↔ A) ↔ (A ↔ A) is a substitution instance of: (A ↔ A) In some deduction systems for propositional logic, a new...

up substitution in Wiktionary, the free dictionary. Substitution may refer to: Substitution (poetry), a variation in poetic scansion Substitution (theatre)...

In mathematical logic, a tautology (from Greek: ταυτολογία) is a formula or assertion that is true in every possible interpretation. An example is "x=y...

First-order logic—also known as predicate logic, quantificational logic, and first-order predicate calculus—is a collection of formal systems used in...

in mathematical logic for expressing computation based on function abstraction and application using variable binding and substitution. It is a universal...

{\displaystyle B'} yields B {\displaystyle B} after substitution, then attempts to prove A {\displaystyle A} by substitution. chaining forward: given expression A →...

Combinatory logic is a notation to eliminate the need for quantified variables in mathematical logic. It was introduced by Moses Schönfinkel and Haskell...

instead of quantifying over substitution instances. Some authors also admit propositional variables in first-order logic, which must then also be interpreted...

Logic is the study of correct reasoning. It includes both formal and informal logic. Formal logic is the study of deductively valid inferences or logical...

abstract machines, predicate logic, and symbolic computation. A simple example of a lambda calculus with explicit substitution is "λx", which adds one new...