What is Isabelle?
Isabelle is a generic proof assistant. It allows mathematical formulas to be expressed in a formal language and provides tools for proving those formulas in a logical calculus. Isabelle was originally developed at the University of Cambridge and Technische Universität München, but now includes numerous contributions from institutions and individuals worldwide. See the Isabelle overview for a brief introduction.
Now available: Isabelle2016-1 (December 2016)
Download for Linux
Download for Windows (32bit)
Download for Mac OS XSome notable changes:
- Improved Isabelle/jEdit Prover IDE: more support for formal text structure, more visual feedback.
- The Isabelle/ML IDE can load Isabelle/Pure into itself.
- Improved Isar proof and specification elements.
- HOL codatatype specifications: new commands for corecursive functions.
- HOL tools: new Argo SMT solver, experimental Nunchaku model finder.
- HOL library: improved HOL-Number_Theory and HOL-Library, especially theory Multiset.
- Reorganization of HOL-Probability versus and HOL-Analysis, with many new theorems ported from HOL-Light.
- Improved management of Poly/ML 5.6 processes and cumulative heap files.
See also the cumulative NEWS.
Distribution & Support
Isabelle is distributed for free under a conglomerate of open-source licenses, but the main code-base is subject to BSD-style regulations. The application bundles include source and binary packages and documentation, see the detailed installation instructions. A vast collection of Isabelle examples and applications is available from the Archive of Formal Proofs.
Support is available by ample documentation, the Isabelle community Wiki, Stack Overflow, and in particular the following mailing lists:
- isabelle-users@cl.cam.ac.uk provides a forum for Isabelle users to discuss problems, exchange information, and make announcements. Users of official Isabelle releases should subscribe or see the archive (also available via Google groups and Narkive).
- isabelle-dev@in.tum.de covers the Isabelle development process, including intermediate repository versions, and administrative issues concerning the website or testing infrastructure. Early adopters of development snapshots or repository versions should subscribe or see the archive (also available at mail-archive.com).