1 set "baseuri" "cic:/matita/TPTP/ROB002-1".
2 include "logic/equality.ma".
3 (* Inclusion of: ROB002-1.p *)
4 (* -------------------------------------------------------------------------- *)
5 (* File : ROB002-1 : TPTP v3.1.1. Released v1.0.0. *)
6 (* Domain : Robbins Algebra *)
7 (* Problem : --X = X => Boolean *)
8 (* Version : [Win90] (equality) axioms. *)
9 (* English : If --X = X then the algebra is Boolean. *)
10 (* Refs : [HMT71] Henkin et al. (1971), Cylindrical Algebras *)
11 (* : [Win90] Winker (1990), Robbins Algebra: Conditions that make a *)
12 (* Source : [Win90] *)
13 (* Names : Lemma 2.1 [Win90] *)
14 (* Status : Unsatisfiable *)
15 (* Rating : 0.00 v2.2.1, 0.11 v2.2.0, 0.14 v2.1.0, 0.13 v2.0.0 *)
16 (* Syntax : Number of clauses : 5 ( 0 non-Horn; 5 unit; 1 RR) *)
17 (* Number of atoms : 5 ( 5 equality) *)
18 (* Maximal clause size : 1 ( 1 average) *)
19 (* Number of predicates : 1 ( 0 propositional; 2-2 arity) *)
20 (* Number of functors : 4 ( 2 constant; 0-2 arity) *)
21 (* Number of variables : 8 ( 0 singleton) *)
22 (* Maximal term depth : 6 ( 3 average) *)
23 (* Comments : Commutativity, associativity, and Huntington's axiom *)
24 (* axiomatize Boolean algebra. *)
25 (* -------------------------------------------------------------------------- *)
26 (* ----Include axioms for Robbins algebra *)
27 (* Inclusion of: Axioms/ROB001-0.ax *)
28 (* -------------------------------------------------------------------------- *)
29 (* File : ROB001-0 : TPTP v3.1.1. Released v1.0.0. *)
30 (* Domain : Robbins algebra *)
31 (* Axioms : Robbins algebra axioms *)
32 (* Version : [Win90] (equality) axioms. *)
34 (* Refs : [HMT71] Henkin et al. (1971), Cylindrical Algebras *)
35 (* : [Win90] Winker (1990), Robbins Algebra: Conditions that make a *)
36 (* Source : [OTTER] *)
37 (* Names : Lemma 2.2 [Win90] *)
39 (* Syntax : Number of clauses : 3 ( 0 non-Horn; 3 unit; 0 RR) *)
40 (* Number of literals : 3 ( 3 equality) *)
41 (* Maximal clause size : 1 ( 1 average) *)
42 (* Number of predicates : 1 ( 0 propositional; 2-2 arity) *)
43 (* Number of functors : 2 ( 0 constant; 1-2 arity) *)
44 (* Number of variables : 7 ( 0 singleton) *)
45 (* Maximal term depth : 6 ( 3 average) *)
47 (* -------------------------------------------------------------------------- *)
48 (* -------------------------------------------------------------------------- *)
49 (* -------------------------------------------------------------------------- *)
50 theorem prove_huntingtons_axiom:
53 \forall add:\forall _:Univ.\forall _:Univ.Univ.
55 \forall negate:\forall _:Univ.Univ.
56 \forall H0:\forall X:Univ.eq Univ (negate (negate X)) X.
57 \forall H1:\forall X:Univ.\forall Y:Univ.eq Univ (negate (add (negate (add X Y)) (negate (add X (negate Y))))) X.
58 \forall H2:\forall X:Univ.\forall Y:Univ.\forall Z:Univ.eq Univ (add (add X Y) Z) (add X (add Y Z)).
59 \forall H3:\forall X:Univ.\forall Y:Univ.eq Univ (add X Y) (add Y X).eq Univ (add (negate (add a (negate b))) (negate (add (negate a) (negate b)))) b
62 auto paramodulation timeout=600.
66 (* -------------------------------------------------------------------------- *)