Type theory | Logic in computer science | Constructivism (mathematics) | Foundations of mathematics | Intuitionism

Intuitionistic type theory

Intuitionistic type theory (also known as constructive type theory, or Martin-Löf type theory) is a type theory and an alternative foundation of mathematics.Intuitionistic type theory was created by Per Martin-Löf, a Swedish mathematician and philosopher, who first published it in 1972. There are multiple versions of the type theory: Martin-Löf proposed both intensional and extensional variants of the theory and early impredicative versions, shown to be inconsistent by Girard's paradox, gave way to predicative versions. However, all versions keep the core design of constructive logic using dependent types. (Wikipedia).

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LambdaConf 2015 - Introduction to Intuitionistic Type Theory Vlad Patryshev

Traditionally, in Computer Science, sets are assumed to be the basis of a type theory, together with Boolean logic. In this version of type theory, we do not need sets or Boolean logic; intuitionism is enough ("no principle of excluded middle required"). The underlying math is Topos Theory

From playlist LambdaConf 2015

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LambdaConf 2015 - Type Theory and its Meaning Explanations Jon Sterling

At the heart of intuitionistic type theory lies an intuitive semantics called the “meaning explanations." Crucially, when meaning explanations are taken as definitive for type theory, the core notion is no longer “proof” but “verification”. We’ll explore how type theories of this sort aris

From playlist LambdaConf 2015

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What is Reductionism?

There are two different types of reductionism. One is called methodological reductionism, the other one theory reductionism. Methodological reductionism is about the properties of the real world. It’s about taking things apart into smaller things and finding that the smaller things determ

From playlist Philosophy of Science

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What are the Types of Numbers? Real vs. Imaginary, Rational vs. Irrational

We've mentioned in passing some different ways to classify numbers, like rational, irrational, real, imaginary, integers, fractions, and more. If this is confusing, then take a look at this handy-dandy guide to the taxonomy of numbers! It turns out we can use a hierarchical scheme just lik

From playlist Algebra 1 & 2

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Tests, Games, and Martin-Lof's Meaning Explanations for Intuitionistic Type Theory - Peter Dybjer

Peter Dybjer November 30, 2012 For more videos, visit http://video.ias.edu

From playlist Mathematics

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Peter Dybjer: Intuitionistic Type Theory (Lecture II)

The lecture was held within the framework of the Hausdorff Trimester Program: Types, Sets and Constructions

From playlist HIM Lectures: Trimester Program "Types, Sets and Constructions"

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Peter Dybjer: Intuitionistic Type Theory (Lecture III)

The lecture was held within the framework of the Hausdorff Trimester Program: Types, Sets and Constructions

From playlist HIM Lectures: Trimester Program "Types, Sets and Constructions"

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Peter Dybjer: Intuitionistic Type Theory (Lecture I)

The lecture was held within the framework of the Hausdorff Trimester Program: Types, Sets and Constructions

From playlist HIM Lectures: Trimester Program "Types, Sets and Constructions"

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Heyting algebras and Negation

This is a follow up to https://youtu.be/lDhKE2SKF08. In this video we zoom in on Negation and also discuss models such as the 3-valued one for intuitionistic propositional logic. The script I'm using you can find here: https://gist.github.com/Nikolaj-K/1478e66ccc9b7ac2ea565e743c904555

From playlist Logic

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Makoto Fujiwara: Bar theorem and bar recursion for continuous functions with continuous modulus

The lecture was held within the framework of the Hausdorff Trimester Program: Constructive Mathematics. Abstract: (joint work with Tatsuji Kawai) Bar induction is originally discussed by L. E. J. Brouwer under the name of “bar theorem” in his intuitionistic mathematics but first formali

From playlist Workshop: "Constructive Mathematics"

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Anders Mörtberg: Yet Another Cartesian Cubical Type Theory yacctt

The lecture was held within the framework of the Hausdorff Trimester Program: Types, Sets and Constructions. Abstract: I will discuss recent work on developing a Cartesian cubical type theory inspired by the computational semantics of Computational Higher Type Theory of Angiuli et. al. Th

From playlist Workshop: "Types, Homotopy, Type theory, and Verification"

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Martin Hötzel Escardó: Constructive Mathematics in Univalent Type Theory (Lecture II)

The lecture was held within the framework of the Hausdorff Trimester Program: Types, Sets and Constructions

From playlist HIM Lectures: Trimester Program "Types, Sets and Constructions"

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Axioms of Constructive Set Theory Explained

In this video we're going to discuss the various axiom schemes of constructive set theories and how they relate to type theory. I cover BCST, ECST, IKP, KPI, KP, CST, CZF, IZF, Mac Lane, Z and variants equi-consistent to ETCS from category theory, and then of course ZF and ZFC. The text I

From playlist Logic

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Anne Baanen - Computing with or despite the computer - IPAM at UCLA

Recorded 14 February 2023. Anne Baanen of Vrije Universiteit presents "Computing with or despite the computer" at IPAM's Machine Assisted Proofs Workshop. Abstract: I have recently been collaborating on a project where we compute the class number of quadratic number fields, formally verifi

From playlist 2023 Machine Assisted Proofs Workshop

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Discussion - Panel: What is the role of Topos in Information and Communication Technologies?

Mérouane Debbah (Huawei Technologies) Olivia Caramello (Università degli Studi dell'Insubria in Como) Daniel Bennequin (Univ. Paris-Diderot) Thierry Coquand (University of Göteborg) Jean-Claude Belfiore (Huawei France)

From playlist 4th Huawei-IHES Workshop on Mathematical Theories for Information and Communication Technologies

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Dale Miller: Focused proof systems

HYBRID EVENT Recorded during the meeting Linear Logic Winter School" the January 28, 2022 by the Centre International de Rencontres Mathématiques (Marseille, France) Filmmaker: Guillaume Hennenfent Find this video and other talks given by worldwide mathematicians on CIRM's Audiovisual

From playlist Logic and Foundations

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Squashing theories into Heyting algebras

This is the first of two videos on Heyting algebra, Tarski-Lindenbaum and negation: https://gist.github.com/Nikolaj-K/1478e66ccc9b7ac2ea565e743c904555 Followup video: https://youtu.be/ws6vCT7ExTY

From playlist Logic

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Bas Spitters: Modal Dependent Type Theory and the Cubical Model

The lecture was held within the framework of the Hausdorff Trimester Program: Types, Sets and Constructions. Abstract: In recent years we have seen several new models of dependent type theory extended with some form of modal necessity operator, including nominal type theory, guarded and c

From playlist Workshop: "Types, Homotopy, Type theory, and Verification"

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Hugo Herbelin: A constructive proof of dependent choice, compatible with classical logic

The lecture was held within the framework of the Hausdorff Trimester Program: Constructive Mathematics. Abstract: Martin-Löf's type theory has strong existential elimination (dependent sum type) what allows to prove the full axiom of choice. However the theory is intuitionistic. We give

From playlist Workshop: "Constructive Mathematics"

Related pages

Undecidable problem | Homotopy | Negation | Proof assistant | Calculus of constructions | Homotopy type theory | Setoid | Decision problem | Typed lambda calculus | Structural induction | Intensional logic | Extensionality | Rational number | Foundations of mathematics | Unit type | Disjoint union | Coq | Path (topology) | Proof theory | Girard's paradox | Epigram (programming language) | Impredicativity | Point (geometry) | Successor function | Reflexive relation | Integer | Empty type | Real number | Cartesian product | Category theory | Type theory | Principia Mathematica | Record (computer science) | Tuple | Intuitionistic logic | Universal quantification | Law of excluded middle | Value (computer science) | First-order logic | Type checking