**Logical truth** — is one of the most fundamental concepts in logic, and there are different theories on its nature. A logical truth is a statement which is true and remains true under all reinterpretations of its components other than its logical constants. It is… … Wikipedia

**Logical constant** — In symbolic logic, a logical constant of a language L is a symbol that has the same semantic value in all models of (the expressions of) L . Two important types of logical constants are logical connectives and quantifiers. The equality predicate… … Wikipedia

**Logical connective** — This article is about connectives in classical logic. For connectors in natural languages, see discourse connective. For connectives and operators in other logics, see logical constant. For other logical symbols, see table of logic symbols. In… … Wikipedia

**Logical symbols** — Reading logical symbolism frightens many people more than it should. The very term symbolic logic sounds terrifying, and the presence of even a small amount of symbolism may deter many readers from otherwise perfectly intelligible texts. The… … Philosophy dictionary

**Non-logical symbol** — In logic, the formal languages used to create expressions consist of symbols which can be broadly divided into constants and variables. The constants of a language can further be divided into logical symbols and non logical symbols (sometimes… … Wikipedia

**LF (logical framework)** — In type theory, the LF logical framework provides a means to define (or present) logics. It is based on a general treatment of syntax, rules and proofs by means of a dependently typed lambda calculus. Syntax is treated in a style similar to, but… … Wikipedia

**Interpretation (logic)** — An interpretation is an assignment of meaning to the symbols of a formal language. Many formal languages used in mathematics, logic, and theoretical computer science are defined in solely syntactic terms, and as such do not have any meaning until … Wikipedia

**logic, philosophy of** — Philosophical study of the nature and scope of logic. Examples of questions raised in the philosophy of logic are: In virtue of what features of reality are the laws of logic true? ; How do we know the truths of logic? ; and Could the laws of… … Universalium

**First-order logic** — is a formal logical system used in mathematics, philosophy, linguistics, and computer science. It goes by many names, including: first order predicate calculus, the lower predicate calculus, quantification theory, and predicate logic (a less… … Wikipedia

**metalogic** — /met euh loj ik/, n. the logical analysis of the fundamental concepts of logic. [1835 45; META + LOGIC] * * * Study of the syntax and the semantics of formal languages and formal systems. It is related to, but does not include, the formal… … Universalium