Theorem provers are software systems that can find or check proofs for conjectures given in some logic. Research in theorem proving system started with the logical theorist 1955 and has led to a succession of systems since.

Theorem provers are complex software systems that have pushed the envelope of artificial intelligence and programming, and as such they constitute important cultural artefacts.

With the current wave of retirements of the original principal investigators there is good chance that the systems are lost, when their group servers are shut down. This web site aims to preserve the ones we can still get our hands on. This idea is compatible with the Software Heritage initiative, and contributes since it is based on GitHub repositories.

The term "museum" may be sound bit ambitious, since the exhibition and didactic interpretation of the theorem provers is beyond our scope (and perhaps abilities). But the foremost function of a museum is the conservation of artefacts, which is what the "theorem prover museum" project intends to do.

This site is the front-end to a collection of source code repositories for theorem provers (see below). To exhibit your system here or suggest a system for inclusion (most wanted list, systems believed lost), please contact Michael Kohlhase. Contributors, community/contact, project/issues.

Note that it is not the purpose of this site to keep the theorem proving systems running (in many cases the compilers and dependencies have moved on, making this very difficult). But only to archive the source code for academic study. In particular this should lower the barrier of archiving systems here.

**Related Resources**: encyclopedia of proof
systems, Wikipedia page, ... more.

All theorem provers start out as active systems, eventually development gets discontinued as developers retire or move to newer systems. Therefore we also maintain a list of source code repositories of active theorem provers.

The Markgraph Karl Refutation Procedure, a graph-based resolution theorem prover written in Common Lisp

The first theorem prover and model generator for first-order logic with equality from the Argonne group that was widely distributed.

The Prolog Equation Solving System (PRESS) pioneered work on what is now called proof planning.

TPS is an interactive, semi-automatic, and automatic Theorem Proving System for first-order logic and higher-order logic. The subsystem ETPS is designed for interactive use by students in logic courses.

The HOL System is an environment for interactive theorem proving in a higher-order logic. Its most outstanding feature is its high degree of programmability through the meta-language ML.

A Prolog implementation of the proof planner Clam (in the clam2 development branch) and the associated theorem prover, oyster.

Prolog implementation of proof planner with critics, and some higher-order unification, in the v3 branch of Clam.