%------------------------------------------------------------------------------
% File     : LCL531+1 : TPTP v9.0.0. Released v3.3.0.
% Domain   : Logic Calculi (Propositional modal)
% Problem  : Prove axiom m4 from KM5 axiomatization of S5
% Version  : [HC96] axioms.
% English  :

% Refs     : [HC96]  Hughes & Cresswell (1996), A New Introduction to Modal
%          : [Hal]   Halleck (URL), John Halleck's Logic Systems
% Source   : [TPTP]
% Names    :

% Status   : Theorem
% Rating   : 0.15 v9.0.0, 0.17 v8.1.0, 0.22 v7.5.0, 0.28 v7.4.0, 0.23 v7.3.0, 0.24 v7.1.0, 0.26 v7.0.0, 0.27 v6.4.0, 0.35 v6.3.0, 0.29 v6.2.0, 0.36 v6.1.0, 0.40 v6.0.0, 0.43 v5.5.0, 0.56 v5.4.0, 0.54 v5.3.0, 0.63 v5.2.0, 0.45 v5.1.0, 0.43 v5.0.0, 0.50 v4.1.0, 0.52 v4.0.1, 0.48 v4.0.0, 0.50 v3.7.0, 0.40 v3.5.0, 0.37 v3.4.0, 0.53 v3.3.0
% Syntax   : Number of formulae    :   88 (  30 unt;   0 def)
%            Number of atoms       :  155 (  11 equ)
%            Maximal formula atoms :    4 (   1 avg)
%            Number of connectives :   67 (   0   ~;   0   |;   3   &)
%                                         (  49 <=>;  15  =>;   0  <=;   0 <~>)
%            Maximal formula depth :    6 (   3 avg)
%            Maximal term depth    :    5 (   2 avg)
%            Number of predicates  :   61 (  60 usr;  59 prp; 0-2 aty)
%            Number of functors    :    9 (   9 usr;   0 con; 1-2 aty)
%            Number of variables   :  110 ( 110   !;   0   ?)
% SPC      : FOF_THM_RFO_SEQ

% Comments :
%------------------------------------------------------------------------------
%----Include Hilbert's axiomatization of propositional logic
include('Axioms/LCL006+0.ax').
include('Axioms/LCL006+1.ax').
include('Axioms/LCL006+2.ax').
%----Include axioms of modal logic
include('Axioms/LCL007+0.ax').
include('Axioms/LCL007+1.ax').
%----Include axioms for KM5
include('Axioms/LCL007+2.ax').
%------------------------------------------------------------------------------
%----Modal definitions
fof(s1_0_op_possibly,axiom,
    op_possibly ).

fof(s1_0_op_or,axiom,
    op_or ).

fof(s1_0_op_implies,axiom,
    op_implies ).

fof(s1_0_op_strict_implies,axiom,
    op_strict_implies ).

fof(s1_0_op_equiv,axiom,
    op_equiv ).

fof(s1_0_op_strict_equiv,axiom,
    op_strict_equiv ).

%----Conjecture
fof(s1_0_axiom_m4,conjecture,
    axiom_m4 ).

%------------------------------------------------------------------------------