provable sentence

См. также в других словарях:

• Gödel's incompleteness theorems — In mathematical logic, Gödel s incompleteness theorems, proved by Kurt Gödel in 1931, are two theorems stating inherent limitations of all but the most trivial formal systems for arithmetic of mathematical interest. The theorems are of… …   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

• Propositional calculus — In mathematical logic, a propositional calculus or logic (also called sentential calculus or sentential logic) is a formal system in which formulas of a formal language may be interpreted as representing propositions. A system of inference rules… …   Wikipedia

• Proof sketch for Gödel's first incompleteness theorem — This article gives a sketch of a proof of Gödel s first incompleteness theorem. This theorem applies to any formal theory that satisfies certain technical hypotheses which are discussed as needed during the sketch. We will assume for the… …   Wikipedia

• Turing's proof — First published in January 1937 with the title On Computable Numbers, With an Application to the Entscheidungsproblem , Turing s proof was the second proof of the assertion (Alonzo Church proof was first) that some questions are undecidable :… …   Wikipedia

• Original proof of Gödel's completeness theorem — The proof of Gödel s completeness theorem given by Kurt Gödel in his doctoral dissertation of 1929 (and a rewritten version of the dissertation, published as an article in 1930) is not easy to read today; it uses concepts and formalism that are… …   Wikipedia

• Rosser's trick — For the theorem about the sparseness of prime numbers, see Rosser s theorem. For a general introduction to the incompleteness theorems, see Gödel s incompleteness theorems. In mathematical logic, Rosser s trick is a method for proving Gödel s… …   Wikipedia

• Soundness — In mathematical logic, a logical system has the soundness property if and only if its inference rules prove only formulas that are valid with respect to its semantics. In most cases, this comes down to its rules having the property of preserving… …   Wikipedia

• Curry's paradox — For Paul Curry s optical illusion and dissection puzzle, see Missing square puzzle. Curry s paradox is a paradox that occurs in naive set theory or naive logics, and allows the derivation of an arbitrary sentence from a self referring sentence… …   Wikipedia

• 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

• Gödel's completeness theorem — is a fundamental theorem in mathematical logic that establishes a correspondence between semantic truth and syntactic provability in first order logic. It was first proved by Kurt Gödel in 1929. A first order formula is called logically valid if… …   Wikipedia