enumerable language
71Halting problem — In computability theory, the halting problem can be stated as follows: Given a description of a computer program, decide whether the program finishes running or continues to run forever. This is equivalent to the problem of deciding, given a… …
72Admissible rule — In logic, a rule of inference is admissible in a formal system if the set of theorems of the system is closed under the rule. The concept of an admissible rule was introduced by Paul Lorenzen (1955).DefinitionsThe concept of admissibility, as… …
73Turing'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 :… …
74Context-free grammar — In formal language theory, a context free grammar (CFG) is a formal grammar in which every production rule is of the form V → w where V is a single nonterminal symbol, and w is a string of terminals and/or nonterminals (w can be empty). The… …
75Ludwig Wittgenstein — Wittgenstein redirects here. For other uses, see Wittgenstein (disambiguation). Ludwig Wittgenstein Photographed by Ben Richards Swansea, Wales, 1947 Born 26 April 1889 …
76Noam Chomsky — Chomsky redirects here. For other topics with the same name, see Chomsky (disambiguation). Noam Chomsky Noam Chomsky visiting Vancouver, Canada in 2004 …
77metalogic — /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… …
78Rhetoric — This article is about the art of rhetoric in general. For the work by Aristotle, see Rhetoric (Aristotle). Painting depicting a lecture in a knight academy, painted by Pieter Isaacsz or Reinhold Timm for Rosenborg Castle as part of a series of… …
79Interpretation (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 …
80Controlled grammar — Controlled grammars[1] are a class of grammars that extend, usually, the context free grammars with additional controls on the derivations of a sentence in the language. A number of different kinds of controlled grammars exist, the four main… …
