--- /dev/null
+set "baseuri" "cic:/matita/TPTP/LCL255-3".
+include "logic/equality.ma".
+
+(* Inclusion of: LCL255-3.p *)
+
+(* -------------------------------------------------------------------------- *)
+
+(* File : LCL255-3 : TPTP v3.2.0. Released v2.3.0. *)
+
+(* Domain : Logic Calculi (Propositional) *)
+
+(* Problem : Principia Mathematica 3.48 *)
+
+(* Version : [WR27] axioms. *)
+
+(* English : *)
+
+(* Refs : [WR27] Whitehead & Russell (1927), Principia Mathematica *)
+
+(* Source : [SE94] *)
+
+(* Names : Problem 3.48 [WR27] *)
+
+(* Status : Unsatisfiable *)
+
+(* Rating : 0.71 v3.1.0, 0.78 v2.7.0, 0.83 v2.6.0, 1.00 v2.3.0 *)
+
+(* Syntax : Number of clauses : 10 ( 0 non-Horn; 8 unit; 3 RR) *)
+
+(* Number of atoms : 13 ( 2 equality) *)
+
+(* Maximal clause size : 3 ( 1 average) *)
+
+(* Number of predicates : 3 ( 0 propositional; 1-2 arity) *)
+
+(* Number of functors : 8 ( 4 constant; 0-2 arity) *)
+
+(* Number of variables : 18 ( 1 singleton) *)
+
+(* Maximal term depth : 4 ( 3 average) *)
+
+(* Comments : *)
+
+(* -------------------------------------------------------------------------- *)
+
+(* ----Include axioms of propositional logic *)
+
+(* Inclusion of: Axioms/LCL004-0.ax *)
+
+(* ------------------------------------------------------------------------------ *)
+
+(* File : LCL004-0 : TPTP v3.2.0. Released v2.3.0. *)
+
+(* Domain : Logic Calculi (Propositional) *)
+
+(* Axioms : Propositional logic deduction axioms *)
+
+(* Version : [WR27] axioms. *)
+
+(* English : *)
+
+(* Refs : [WR27] Whitehead & Russell (1927), Principia Mathematica *)
+
+(* Source : [WR27] *)
+
+(* Names : *)
+
+(* Status : *)
+
+(* Syntax : Number of clauses : 8 ( 0 non-Horn; 6 unit; 2 RR) *)
+
+(* Number of literals : 11 ( 1 equality) *)
+
+(* Maximal clause size : 3 ( 1 average) *)
+
+(* Number of predicates : 3 ( 0 propositional; 1-2 arity) *)
+
+(* Number of functors : 3 ( 0 constant; 1-2 arity) *)
+
+(* Number of variables : 16 ( 1 singleton) *)
+
+(* Maximal term depth : 4 ( 2 average) *)
+
+(* Comments : This axiomatization follows [WR27], allowing full detachment *)
+
+(* but no chaining (which is a dependant theorem). Compare with *)
+
+(* LCL003-0.ax. *)
+
+(* ------------------------------------------------------------------------------ *)
+
+(* input_clause(rule_3,axiom, *)
+
+(* [++theorem(implies(X,Z)), *)
+
+(* --theorem(implies(X,Y)), *)
+
+(* --theorem(implies(Y,Z))]). *)
+
+(* ------------------------------------------------------------------------------ *)
+
+(* Inclusion of: Axioms/LCL004-1.ax *)
+
+(* -------------------------------------------------------------------------- *)
+
+(* File : LCL004-1 : TPTP v3.2.0. Released v2.3.0. *)
+
+(* Domain : Logic Calculi (Propositional) *)
+
+(* Axioms : Propositional logic deduction axioms for AND *)
+
+(* Version : [WR27] axioms. *)
+
+(* English : *)
+
+(* Refs : [WR27] Whitehead & Russell (1927), Principia Mathematica *)
+
+(* Source : [WR27] *)
+
+(* Names : *)
+
+(* Status : *)
+
+(* Syntax : Number of clauses : 1 ( 0 non-Horn; 1 unit; 0 RR) *)
+
+(* Number of literals : 1 ( 1 equality) *)
+
+(* Maximal clause size : 1 ( 1 average) *)
+
+(* Number of predicates : 1 ( 0 propositional; 2-2 arity) *)
+
+(* Number of functors : 3 ( 0 constant; 1-2 arity) *)
+
+(* Number of variables : 2 ( 0 singleton) *)
+
+(* Maximal term depth : 4 ( 3 average) *)
+
+(* Comments : Requires LCL004-0.ax *)
+
+(* -------------------------------------------------------------------------- *)
+
+(* -------------------------------------------------------------------------- *)
+
+(* -------------------------------------------------------------------------- *)
+theorem prove_this:
+ ∀Univ:Set.∀A:Univ.∀B:Univ.∀C:Univ.∀P:Univ.∀Q:Univ.∀X:Univ.∀Y:Univ.∀myand:∀_:Univ.∀_:Univ.Univ.∀axiomP:∀_:Univ.Prop.∀implies:∀_:Univ.∀_:Univ.Univ.∀not:∀_:Univ.Univ.∀or:∀_:Univ.∀_:Univ.Univ.∀p:Univ.∀q:Univ.∀r:Univ.∀s:Univ.∀theoremP:∀_:Univ.Prop.∀H0:∀P:Univ.∀Q:Univ.eq Univ (myand P Q) (not (or (not P) (not Q))).∀H1:∀X:Univ.∀Y:Univ.∀_:theoremP Y.∀_:theoremP (implies Y X).theoremP X.∀H2:∀X:Univ.∀_:axiomP X.theoremP X.∀H3:∀X:Univ.∀Y:Univ.eq Univ (implies X Y) (or (not X) Y).∀H4:∀A:Univ.∀B:Univ.∀C:Univ.axiomP (implies (implies A B) (implies (or C A) (or C B))).∀H5:∀A:Univ.∀B:Univ.∀C:Univ.axiomP (implies (or A (or B C)) (or B (or A C))).∀H6:∀A:Univ.∀B:Univ.axiomP (implies (or A B) (or B A)).∀H7:∀A:Univ.∀B:Univ.axiomP (implies A (or B A)).∀H8:∀A:Univ.axiomP (implies (or A A) A).theoremP (implies (myand (implies p r) (implies q s)) (implies (or p q) (or r s)))
+.
+intros.
+autobatch depth=5 width=5 size=20 timeout=10;
+try assumption.
+print proofterm.
+qed.
+
+(* -------------------------------------------------------------------------- *)