The E Theorem Prover

[Relax]

Overview

E is a theorem prover for full first-order logic (and now monomorphic higher-order logic)with equality. It accepts a problem specification, typically consisting of a number of clauses or formulas, and a conjecture, again either in clausal or full first-order form. The system will then try to find a formal proof for the conjecture, assuming the axioms.

If a proof is found, the system can provide a detailed list of proof steps that can be individually verified. If the conjecture is existential (i.e. it is of the form "there exists an X with property P"), more recent versions can also provide possible answers (values for X).

Development of E started as part of the E-SETHEO project at TUM. The first public release was in in 1998, and the system has been continuously improved ever since. I believe that E now is one of the most powerful and friendly reasoning systems for first-order logic. The prover has successfully participated in many competitions.

3.0
release

Latest news

E 3.0.03 Shangri-La is now available. The main changes compared to E 2.6 are support for full higher order logic and much improved multicore-scheduling. This release is the cleaned up and debugged version of both the 3.0 and 3.1 pre-release versions that performed well in CASC-J11 and CASC-29 (with some additional extra work). The minor 3.0.03 update fixes a number of problems reported after the original 3.0 release.

The new version is available from the Download page.

[CASC-29 Trophy]

E 3.1 Singbully (pre-release) has won the SLH division (problems from Sledgehammer with a 30 second CPU time limit) of CASC-29. It has also won second places in FOF and third places in UEQ and THF). The official release is subsumed by E 3.0 (which was delayed a lot, but has now been released). The latest unreleased versions are always available at GitHub (but use them at your own risk!).