Tarski's undefinability theorem
E71179
Tarski's undefinability theorem is a fundamental result in mathematical logic showing that, in sufficiently strong formal systems, the notion of truth for the language of the system cannot be defined within that same language.
All labels observed (3)
| Label | Occurrences |
|---|---|
| Tarski's undefinability theorem canonical | 2 |
| Tarski undefinability theorem | 1 |
| Tarski’s undefinability theorem | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T568428 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
Target entity: Tarski's undefinability theorem Context triple: [liar paradox, relatedTo, Tarski's undefinability theorem]
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A.
Hilbert’s program
Hilbert’s program was an influential early-20th-century initiative in the foundations of mathematics that sought to formalize all of mathematics and prove its consistency using finitistic methods.
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B.
Remarks on the Foundations of Mathematics
Remarks on the Foundations of Mathematics is a posthumously published collection of Ludwig Wittgenstein’s later writings that critically examines the nature of mathematical truth, proof, and practice from a philosophical and language-centered perspective.
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C.
The Logical Syntax of Language
The Logical Syntax of Language is Rudolf Carnap’s seminal 1934 work that systematically develops a formal, logical framework for analyzing the structure and rules of scientific languages, helping to found logical empiricism and modern philosophy of language.
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D.
von Neumann paradox in set theory
The von Neumann paradox in set theory is a foundational result showing that, under certain group-theoretic conditions, a set can be decomposed and reassembled into paradoxical subsets of equal “size,” illustrating the counterintuitive consequences of the axiom of choice.
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E.
Russell’s paradox
Russell’s paradox is a foundational logical contradiction in naive set theory that reveals problems with sets that contain themselves, leading to major developments in modern logic and the axiomatization of set theory.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
Target entity: Tarski's undefinability theorem Target entity description: Tarski's undefinability theorem is a fundamental result in mathematical logic showing that, in sufficiently strong formal systems, the notion of truth for the language of the system cannot be defined within that same language.
-
A.
Hilbert’s program
Hilbert’s program was an influential early-20th-century initiative in the foundations of mathematics that sought to formalize all of mathematics and prove its consistency using finitistic methods.
-
B.
Remarks on the Foundations of Mathematics
Remarks on the Foundations of Mathematics is a posthumously published collection of Ludwig Wittgenstein’s later writings that critically examines the nature of mathematical truth, proof, and practice from a philosophical and language-centered perspective.
-
C.
The Logical Syntax of Language
The Logical Syntax of Language is Rudolf Carnap’s seminal 1934 work that systematically develops a formal, logical framework for analyzing the structure and rules of scientific languages, helping to found logical empiricism and modern philosophy of language.
-
D.
von Neumann paradox in set theory
The von Neumann paradox in set theory is a foundational result showing that, under certain group-theoretic conditions, a set can be decomposed and reassembled into paradoxical subsets of equal “size,” illustrating the counterintuitive consequences of the axiom of choice.
-
E.
Russell’s paradox
Russell’s paradox is a foundational logical contradiction in naive set theory that reveals problems with sets that contain themselves, leading to major developments in modern logic and the axiomatization of set theory.
- F. None of above. chosen
Statements (47)
| Predicate | Object |
|---|---|
| instanceOf |
mathematical theorem
ⓘ
result in mathematical logic ⓘ |
| appliesTo |
Peano arithmetic
ⓘ
arithmetically adequate theories ⓘ first-order arithmetic ⓘ formal languages ⓘ sufficiently strong formal systems ⓘ |
| concerns |
definability of semantic concepts
ⓘ
limitations of formal systems ⓘ truth predicates ⓘ |
| consequence |
no formula in the language of arithmetic can capture exactly the Gödel numbers of all true arithmetic sentences
ⓘ
truth in arithmetic is not arithmetically definable ⓘ truth is strictly stronger than provability in arithmetic ⓘ |
| field |
mathematical logic
ⓘ
metalogic ⓘ model theory ⓘ |
| formalizes | impossibility of defining a global truth predicate for a language within itself ⓘ |
| historicalPeriod | 20th-century logic ⓘ |
| holdsIn | any consistent, sufficiently strong, effectively axiomatizable theory extending Robinson arithmetic ⓘ |
| implies |
hierarchy between object language and metalanguage
ⓘ
nonexistence of an internal truth predicate for arithmetic ⓘ semantic notions like truth may require a stronger metalanguage ⓘ |
| influenced |
philosophy of language
ⓘ
philosophy of mathematics ⓘ theories of truth in analytic philosophy ⓘ |
| mainTopic |
formal theories of truth
ⓘ
undefinability of truth ⓘ |
| motivated |
development of formal truth theories
ⓘ
distinction between object language and metalanguage in logic ⓘ study of truth hierarchies ⓘ |
| namedAfter | Alfred Tarski ⓘ |
| relatedTo |
Gödel's incompleteness theorems
ⓘ
Tarskian object-language/metalanguage distinction ⓘ
surface form:
Tarski's hierarchy of languages
Tarskian object-language/metalanguage distinction ⓘ
surface form:
Tarski's semantic conception of truth
Tarski–Mostowski–Robinson theorem ⓘ definability theory ⓘ liar paradox ⓘ |
| requires |
effective axiomatizability of the theory
ⓘ
sufficient expressive power to represent arithmetic ⓘ |
| statesThat |
no arithmetically definable predicate in the language of arithmetic can coincide with the truth predicate for arithmetic
ⓘ
there is no formula in the language of arithmetic that defines the set of all true arithmetic sentences ⓘ truth for the language of a sufficiently strong theory cannot be defined within that same language ⓘ |
| typeOf |
metatheorem about formal theories
ⓘ
undefinability result ⓘ |
| uses |
arithmetization of syntax
ⓘ
diagonalization ⓘ self-referential sentences ⓘ |
How these facts were elicited
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Subject: Tarski's undefinability theorem Description of subject: Tarski's undefinability theorem is a fundamental result in mathematical logic showing that, in sufficiently strong formal systems, the notion of truth for the language of the system cannot be defined within that same language.
Referenced by (4)
Full triples — surface form annotated when it differs from this entity's canonical label.