%--------------------------------------------------------------------------
% File     : PLA001-0 : TPTP v9.0.0. Released v1.0.0.
% Domain   : Planning (Blocks world)
% Axioms   : Blocks world axioms
% Version  : [SE94] axioms.
% English  :

% Refs     : [Sus73] Sussman (1973), A Computational Model of Skill Acquisi
%          : [SE94]  Segre & Elkan (1994), A High-Performance Explanation-B
% Source   : [SE94]
% Names    :

% Status   : Satisfiable
% Syntax   : Number of clauses     :   10 (   0 unt;   0 nHn;   8 RR)
%            Number of literals    :   31 (   0 equ;  21 neg)
%            Maximal clause size   :    4 (   3 avg)
%            Maximal term depth    :    3 (   1 avg)
%            Number of predicates  :    2 (   2 usr;   0 prp; 2-2 aty)
%            Number of functors    :    9 (   9 usr;   2 con; 0-2 aty)
%            Number of variables   :   33 (   3 sgn)
% SPC      : 

% Comments : The axioms are a reconstruction of the situation calculus
%            blocks world as in [Sus73].
%--------------------------------------------------------------------------
cnf(and_definition,axiom,
    ( holds(and(X,Y),State)
    | ~ holds(X,State)
    | ~ holds(Y,State) ) ).

cnf(pickup_1,axiom,
    ( holds(holding(X),do(pickup(X),State))
    | ~ holds(empty,State)
    | ~ holds(clear(X),State)
    | ~ differ(X,table) ) ).

cnf(pickup_2,axiom,
    ( holds(clear(Y),do(pickup(X),State))
    | ~ holds(on(X,Y),State)
    | ~ holds(clear(X),State)
    | ~ holds(empty,State) ) ).

cnf(pickup_3,axiom,
    ( holds(on(X,Y),do(pickup(Z),State))
    | ~ holds(on(X,Y),State)
    | ~ differ(X,Z) ) ).

cnf(pickup_4,axiom,
    ( holds(clear(X),do(pickup(Z),State))
    | ~ holds(clear(X),State)
    | ~ differ(X,Z) ) ).

cnf(putdown_1,axiom,
    ( holds(empty,do(putdown(X,Y),State))
    | ~ holds(holding(X),State)
    | ~ holds(clear(Y),State) ) ).

cnf(putdown_2,axiom,
    ( holds(on(X,Y),do(putdown(X,Y),State))
    | ~ holds(holding(X),State)
    | ~ holds(clear(Y),State) ) ).

cnf(putdown_3,axiom,
    ( holds(clear(X),do(putdown(X,Y),State))
    | ~ holds(holding(X),State)
    | ~ holds(clear(Y),State) ) ).

cnf(putdown_4,axiom,
    ( holds(on(X,Y),do(putdown(Z,W),State))
    | ~ holds(on(X,Y),State) ) ).

cnf(putdown_5,axiom,
    ( holds(clear(Z),do(putdown(X,Y),State))
    | ~ holds(clear(Z),State)
    | ~ differ(Z,Y) ) ).

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