Isabelle
Isabelle-92
Isabelle-93

    A generic theorem prover with support for
   several object-logics, developed by Lawrence C. Paulson
    in collaboration with <Tobias
   Nipkow> at the Technical
   University of Munich.

   A system of type classes allows polymorphic object-logics
   with overloading and automatic type inference.

   Isabelle supports first-order logic - constructive and
   classical versions; higher-order logic, similar to Gordon's
   HOL; Zermelo Fränkel set theory; an extensional version
   of Martin Löf's type theory, the classical first-order
   sequent calculus, LK; the modal logics T, S4, and
   S43; and Logic for Computable Functions.

   An object logic's syntax and inference rules are specified
   declaratively allowing single-step proof construction.
   Proof procedures can be expressed using "tactics" and
   "tacticals".  Isabelle provides control structures for
   expressing search procedures and generic tools such as
   simplifiers and classical theorem provers which can be applied
   to object-logics.  Isabelle is built on top of Standard ML
   and uses its user interface.

   <http://cl.cam.ac.uk/Research/HVG/Isabelle/>.

   Mailing list: [email protected].

   ["tactics"?  "tacticals"?]

   (1999-07-26)