# Category: Free theorem provers

Prover9
Prover9 is an automated theorem prover for first-order and equational logic developed by William McCune.
SNARK (theorem prover)
SNARK, (SRI's New Automated Reasoning Kit), is a theorem prover for multi-sorted first-order logic intended for applications in artificial intelligence and software engineering, developed at SRI Inter
Models And Counter-Examples
Mace stands for "Models And Counter-Examples", and is a model finder. Most automated theorem provers try to perform a proof by refutation on the clause normal form of the proof problem, by showing tha
Paradox is a finite-domain model finder for pure first-order logic (FOL) with equality developed by Koen Lindström Claessen and Niklas Sörensson at the Chalmers University of Technology. It can a part
Isabelle (proof assistant)
The Isabelle automated theorem prover is a higher-order logic (HOL) theorem prover, written in Standard ML and Scala. As an LCF-style theorem prover, it is based on a small logical core (kernel) to in
ACL2
ACL2 ("A Computational Logic for Applicative Common Lisp") is a software system consisting of a programming language, created by Timothy Still it was an extensible theory in a first-order logic, and a
SPASS
SPASS is an automated theorem prover for first-order logic with equality developed at the Max Planck Institute for Computer Science and using the superposition calculus. The name originally stood for
Metamath
Metamath is a formal language and an associated computer program (a proof checker) for archiving, verifying, and studying mathematical proofs. Several databases of proved theorems have been developed
KeY
The KeY tool is used in formal verification of Java programs. It accepts specifications written in the Java Modeling Language to Java source files. These are transformed into theorems of dynamic logic
Prototype Verification System
The Prototype Verification System (PVS) is a specification language integrated with support tools and an automated theorem prover, developed at the Computer Science Laboratory of SRI International in
Jape (software)
Jape is a configurable, graphical proof assistant, originally developed by Richard Bornat at Queen Mary, University of London and Bernard Sufrin the University of Oxford. It allows user to define a lo
Matita
Matitais an experimental proof assistant under development at the Computer Science Department of the University of Bologna. It is a tool aiding the development of formal proofs by man-machine collabor
E (theorem prover)
E is a high-performance theorem prover for full first-order logic with equality. It is based on the equational superposition calculus and uses a purely equational paradigm. It has been integrated into
Coq
Coq is an interactive theorem prover first released in 1989. It allows for expressing mathematical assertions, mechanically checks proofs of these assertions, helps find formal proofs, and extracts a
PhoX
In automated theorem proving, PhoX is a proof assistant based on higher-order logic which is eXtensible. The user gives PhoX an initial goal and guides it through subgoals and evidence to prove that g
Otter (theorem prover)
Otter is an automated theorem prover developed by William McCune at Argonne National Laboratory in Illinois. Otter was the first widely distributed, high-performance theorem prover for first-order log
HOL Light
HOL Light is a member of the HOL theorem prover family. Like the other members, it is a proof assistant for classical higher order logic. Compared with other HOL systems, HOL Light is intended to have