0.00/0.12 % Problem : theBenchmark.p : TPTP v0.0.0. Released v0.0.0. 0.12/0.13 % Command : twee %s --tstp --casc --quiet --explain-encoding --conditional-encoding if --smaller --drop-non-horn 0.13/0.34 % Computer : n005.cluster.edu 0.13/0.34 % Model : x86_64 x86_64 0.13/0.34 % CPU : Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz 0.13/0.34 % Memory : 8042.1875MB 0.13/0.34 % OS : Linux 3.10.0-693.el7.x86_64 0.13/0.34 % CPULimit : 180 0.13/0.34 % DateTime : Thu Aug 29 12:54:03 EDT 2019 0.13/0.34 % CPUTime : 5.85/6.03 % SZS status Unsatisfiable 5.85/6.03 5.85/6.04 % SZS output start Proof 5.85/6.04 Take the following subset of the input axioms: 5.85/6.04 fof(associativity, axiom, ![X, Y, Z]: multiply(multiply(X, Y), Z)=multiply(X, multiply(Y, Z))). 5.85/6.04 fof(associativity_of_glb, axiom, ![X, Y, Z]: greatest_lower_bound(X, greatest_lower_bound(Y, Z))=greatest_lower_bound(greatest_lower_bound(X, Y), Z)). 5.85/6.04 fof(associativity_of_lub, axiom, ![X, Y, Z]: least_upper_bound(X, least_upper_bound(Y, Z))=least_upper_bound(least_upper_bound(X, Y), Z)). 5.85/6.04 fof(glb_absorbtion, axiom, ![X, Y]: greatest_lower_bound(X, least_upper_bound(X, Y))=X). 5.85/6.04 fof(left_identity, axiom, ![X]: X=multiply(identity, X)). 5.85/6.04 fof(left_inverse, axiom, ![X]: multiply(inverse(X), X)=identity). 5.85/6.04 fof(lub_absorbtion, axiom, ![X, Y]: X=least_upper_bound(X, greatest_lower_bound(X, Y))). 5.85/6.04 fof(monotony_glb1, axiom, ![X, Y, Z]: multiply(X, greatest_lower_bound(Y, Z))=greatest_lower_bound(multiply(X, Y), multiply(X, Z))). 5.85/6.04 fof(monotony_glb2, axiom, ![X, Y, Z]: greatest_lower_bound(multiply(Y, X), multiply(Z, X))=multiply(greatest_lower_bound(Y, Z), X)). 5.85/6.04 fof(monotony_lub1, axiom, ![X, Y, Z]: least_upper_bound(multiply(X, Y), multiply(X, Z))=multiply(X, least_upper_bound(Y, Z))). 5.85/6.04 fof(monotony_lub2, axiom, ![X, Y, Z]: least_upper_bound(multiply(Y, X), multiply(Z, X))=multiply(least_upper_bound(Y, Z), X)). 5.85/6.04 fof(p20x_1, hypothesis, identity=inverse(identity)). 5.85/6.04 fof(p20x_2, hypothesis, ![X]: inverse(inverse(X))=X). 5.85/6.04 fof(p20x_3, hypothesis, ![X, Y]: multiply(inverse(Y), inverse(X))=inverse(multiply(X, Y))). 5.85/6.04 fof(prove_20x, negated_conjecture, greatest_lower_bound(least_upper_bound(a, identity), least_upper_bound(inverse(a), identity))!=identity). 5.85/6.04 fof(symmetry_of_glb, axiom, ![X, Y]: greatest_lower_bound(Y, X)=greatest_lower_bound(X, Y)). 5.85/6.04 fof(symmetry_of_lub, axiom, ![X, Y]: least_upper_bound(X, Y)=least_upper_bound(Y, X)). 5.85/6.04 5.85/6.04 Now clausify the problem and encode Horn clauses using encoding 3 of 5.85/6.04 http://www.cse.chalmers.se/~nicsma/papers/horn.pdf. 5.85/6.04 We repeatedly replace C & s=t => u=v by the two clauses: 5.85/6.04 fresh(y, y, x1...xn) = u 5.85/6.04 C => fresh(s, t, x1...xn) = v 5.85/6.04 where fresh is a fresh function symbol and x1..xn are the free 5.85/6.04 variables of u and v. 5.85/6.04 A predicate p(X) is encoded as p(X)=true (this is sound, because the 5.85/6.04 input problem has no model of domain size 1). 5.85/6.04 5.85/6.04 The encoding turns the above axioms into the following unit equations and goals: 5.85/6.04 5.85/6.04 Axiom 1 (left_inverse): multiply(inverse(X), X) = identity. 5.85/6.04 Axiom 2 (associativity): multiply(multiply(X, Y), Z) = multiply(X, multiply(Y, Z)). 5.85/6.04 Axiom 3 (left_identity): X = multiply(identity, X). 5.85/6.04 Axiom 4 (symmetry_of_lub): least_upper_bound(X, Y) = least_upper_bound(Y, X). 5.85/6.04 Axiom 5 (glb_absorbtion): greatest_lower_bound(X, least_upper_bound(X, Y)) = X. 5.85/6.04 Axiom 6 (lub_absorbtion): X = least_upper_bound(X, greatest_lower_bound(X, Y)). 5.85/6.04 Axiom 7 (monotony_glb1): multiply(X, greatest_lower_bound(Y, Z)) = greatest_lower_bound(multiply(X, Y), multiply(X, Z)). 5.85/6.04 Axiom 8 (symmetry_of_glb): greatest_lower_bound(X, Y) = greatest_lower_bound(Y, X). 5.85/6.04 Axiom 9 (monotony_lub2): least_upper_bound(multiply(X, Y), multiply(Z, Y)) = multiply(least_upper_bound(X, Z), Y). 5.85/6.04 Axiom 10 (monotony_glb2): greatest_lower_bound(multiply(X, Y), multiply(Z, Y)) = multiply(greatest_lower_bound(X, Z), Y). 5.85/6.04 Axiom 11 (monotony_lub1): least_upper_bound(multiply(X, Y), multiply(X, Z)) = multiply(X, least_upper_bound(Y, Z)). 5.85/6.04 Axiom 12 (associativity_of_glb): greatest_lower_bound(X, greatest_lower_bound(Y, Z)) = greatest_lower_bound(greatest_lower_bound(X, Y), Z). 5.85/6.04 Axiom 13 (associativity_of_lub): least_upper_bound(X, least_upper_bound(Y, Z)) = least_upper_bound(least_upper_bound(X, Y), Z). 5.85/6.04 Axiom 14 (p20x_3): multiply(inverse(X), inverse(Y)) = inverse(multiply(Y, X)). 5.85/6.04 Axiom 15 (p20x_1): identity = inverse(identity). 5.85/6.04 Axiom 16 (p20x_2): inverse(inverse(X)) = X. 5.85/6.04 5.85/6.04 Lemma 17: least_upper_bound(Y, multiply(X, Y)) = multiply(least_upper_bound(X, identity), Y). 5.85/6.04 Proof: 5.85/6.04 least_upper_bound(Y, multiply(X, Y)) 5.85/6.04 = { by axiom 3 (left_identity) } 5.85/6.04 least_upper_bound(multiply(identity, Y), multiply(X, Y)) 5.85/6.04 = { by axiom 9 (monotony_lub2) } 5.85/6.04 multiply(least_upper_bound(identity, X), Y) 5.85/6.04 = { by axiom 4 (symmetry_of_lub) } 5.85/6.04 multiply(least_upper_bound(X, identity), Y) 5.85/6.04 5.85/6.04 Lemma 18: multiply(X, identity) = X. 5.85/6.04 Proof: 5.85/6.04 multiply(X, identity) 5.85/6.04 = { by axiom 16 (p20x_2) } 5.85/6.04 inverse(inverse(multiply(X, identity))) 5.85/6.04 = { by axiom 14 (p20x_3) } 5.85/6.04 inverse(multiply(inverse(identity), inverse(X))) 5.85/6.04 = { by axiom 15 (p20x_1) } 5.85/6.04 inverse(multiply(identity, inverse(X))) 5.85/6.04 = { by axiom 3 (left_identity) } 5.85/6.04 inverse(inverse(X)) 5.85/6.04 = { by axiom 16 (p20x_2) } 5.85/6.04 X 5.85/6.04 5.85/6.04 Lemma 19: multiply(inverse(X), least_upper_bound(X, identity)) = least_upper_bound(identity, inverse(X)). 5.85/6.04 Proof: 5.85/6.04 multiply(inverse(X), least_upper_bound(X, identity)) 5.85/6.04 = { by axiom 11 (monotony_lub1) } 5.85/6.04 least_upper_bound(multiply(inverse(X), X), multiply(inverse(X), identity)) 5.85/6.04 = { by axiom 1 (left_inverse) } 5.85/6.04 least_upper_bound(identity, multiply(inverse(X), identity)) 5.85/6.04 = { by lemma 17 } 5.85/6.04 multiply(least_upper_bound(inverse(X), identity), identity) 5.85/6.04 = { by lemma 18 } 5.85/6.04 least_upper_bound(inverse(X), identity) 5.85/6.04 = { by axiom 4 (symmetry_of_lub) } 5.85/6.04 least_upper_bound(identity, inverse(X)) 5.85/6.04 5.85/6.04 Lemma 20: greatest_lower_bound(Y, multiply(X, Y)) = multiply(greatest_lower_bound(X, identity), Y). 5.85/6.04 Proof: 5.85/6.04 greatest_lower_bound(Y, multiply(X, Y)) 5.85/6.04 = { by axiom 3 (left_identity) } 5.85/6.04 greatest_lower_bound(multiply(identity, Y), multiply(X, Y)) 5.85/6.04 = { by axiom 10 (monotony_glb2) } 5.85/6.04 multiply(greatest_lower_bound(identity, X), Y) 5.85/6.04 = { by axiom 8 (symmetry_of_glb) } 5.85/6.04 multiply(greatest_lower_bound(X, identity), Y) 5.85/6.04 5.85/6.04 Lemma 21: multiply(X, inverse(X)) = identity. 5.85/6.04 Proof: 5.85/6.04 multiply(X, inverse(X)) 5.85/6.04 = { by axiom 16 (p20x_2) } 5.85/6.04 multiply(inverse(inverse(X)), inverse(X)) 5.85/6.04 = { by axiom 1 (left_inverse) } 5.85/6.04 identity 5.85/6.04 5.85/6.04 Lemma 22: multiply(inverse(X), greatest_lower_bound(X, identity)) = greatest_lower_bound(identity, inverse(X)). 5.85/6.04 Proof: 5.85/6.04 multiply(inverse(X), greatest_lower_bound(X, identity)) 5.85/6.04 = { by axiom 7 (monotony_glb1) } 5.85/6.04 greatest_lower_bound(multiply(inverse(X), X), multiply(inverse(X), identity)) 5.85/6.04 = { by axiom 1 (left_inverse) } 5.85/6.04 greatest_lower_bound(identity, multiply(inverse(X), identity)) 5.85/6.04 = { by lemma 20 } 5.85/6.04 multiply(greatest_lower_bound(inverse(X), identity), identity) 5.85/6.04 = { by lemma 18 } 5.85/6.04 greatest_lower_bound(inverse(X), identity) 5.85/6.04 = { by axiom 8 (symmetry_of_glb) } 5.85/6.04 greatest_lower_bound(identity, inverse(X)) 5.85/6.04 5.85/6.04 Lemma 23: multiply(least_upper_bound(identity, inverse(X)), greatest_lower_bound(X, identity)) = multiply(greatest_lower_bound(X, identity), least_upper_bound(identity, inverse(X))). 5.85/6.04 Proof: 5.85/6.04 multiply(least_upper_bound(identity, inverse(X)), greatest_lower_bound(X, identity)) 5.85/6.04 = { by axiom 4 (symmetry_of_lub) } 5.85/6.04 multiply(least_upper_bound(inverse(X), identity), greatest_lower_bound(X, identity)) 5.85/6.04 = { by lemma 17 } 5.85/6.04 least_upper_bound(greatest_lower_bound(X, identity), multiply(inverse(X), greatest_lower_bound(X, identity))) 5.85/6.04 = { by lemma 18 } 5.85/6.04 least_upper_bound(multiply(greatest_lower_bound(X, identity), identity), multiply(inverse(X), greatest_lower_bound(X, identity))) 5.85/6.04 = { by lemma 22 } 5.85/6.04 least_upper_bound(multiply(greatest_lower_bound(X, identity), identity), greatest_lower_bound(identity, inverse(X))) 5.85/6.04 = { by axiom 8 (symmetry_of_glb) } 5.85/6.04 least_upper_bound(multiply(greatest_lower_bound(X, identity), identity), greatest_lower_bound(inverse(X), identity)) 5.85/6.04 = { by lemma 21 } 5.85/6.04 least_upper_bound(multiply(greatest_lower_bound(X, identity), identity), greatest_lower_bound(inverse(X), multiply(X, inverse(X)))) 5.85/6.04 = { by lemma 20 } 5.85/6.04 least_upper_bound(multiply(greatest_lower_bound(X, identity), identity), multiply(greatest_lower_bound(X, identity), inverse(X))) 5.85/6.04 = { by axiom 11 (monotony_lub1) } 5.85/6.04 multiply(greatest_lower_bound(X, identity), least_upper_bound(identity, inverse(X))) 5.85/6.04 5.85/6.04 Lemma 24: least_upper_bound(greatest_lower_bound(X, identity), greatest_lower_bound(identity, inverse(X))) = multiply(least_upper_bound(X, identity), greatest_lower_bound(identity, inverse(X))). 5.85/6.04 Proof: 5.85/6.04 least_upper_bound(greatest_lower_bound(X, identity), greatest_lower_bound(identity, inverse(X))) 5.85/6.04 = { by lemma 22 } 5.85/6.04 least_upper_bound(greatest_lower_bound(X, identity), multiply(inverse(X), greatest_lower_bound(X, identity))) 5.85/6.04 = { by axiom 4 (symmetry_of_lub) } 5.85/6.04 least_upper_bound(multiply(inverse(X), greatest_lower_bound(X, identity)), greatest_lower_bound(X, identity)) 5.85/6.04 = { by axiom 3 (left_identity) } 5.85/6.04 least_upper_bound(multiply(inverse(X), greatest_lower_bound(X, identity)), multiply(identity, greatest_lower_bound(X, identity))) 5.85/6.04 = { by lemma 21 } 5.85/6.04 least_upper_bound(multiply(inverse(X), greatest_lower_bound(X, identity)), multiply(multiply(X, inverse(X)), greatest_lower_bound(X, identity))) 5.85/6.04 = { by axiom 2 (associativity) } 5.85/6.04 least_upper_bound(multiply(inverse(X), greatest_lower_bound(X, identity)), multiply(X, multiply(inverse(X), greatest_lower_bound(X, identity)))) 5.85/6.04 = { by lemma 17 } 5.85/6.04 multiply(least_upper_bound(X, identity), multiply(inverse(X), greatest_lower_bound(X, identity))) 5.85/6.04 = { by lemma 22 } 5.85/6.04 multiply(least_upper_bound(X, identity), greatest_lower_bound(identity, inverse(X))) 5.85/6.04 5.85/6.04 Goal 1 (prove_20x): greatest_lower_bound(least_upper_bound(a, identity), least_upper_bound(inverse(a), identity)) = identity. 5.85/6.04 Proof: 5.85/6.04 greatest_lower_bound(least_upper_bound(a, identity), least_upper_bound(inverse(a), identity)) 5.85/6.04 = { by lemma 18 } 5.85/6.04 greatest_lower_bound(multiply(least_upper_bound(a, identity), identity), least_upper_bound(inverse(a), identity)) 5.85/6.04 = { by lemma 21 } 5.85/6.04 greatest_lower_bound(multiply(least_upper_bound(a, identity), identity), least_upper_bound(inverse(a), multiply(a, inverse(a)))) 5.85/6.04 = { by lemma 17 } 5.85/6.04 greatest_lower_bound(multiply(least_upper_bound(a, identity), identity), multiply(least_upper_bound(a, identity), inverse(a))) 5.85/6.04 = { by axiom 7 (monotony_glb1) } 5.85/6.04 multiply(least_upper_bound(a, identity), greatest_lower_bound(identity, inverse(a))) 5.85/6.04 = { by lemma 24 } 5.85/6.04 least_upper_bound(greatest_lower_bound(a, identity), greatest_lower_bound(identity, inverse(a))) 5.85/6.04 = { by axiom 5 (glb_absorbtion) } 5.85/6.04 greatest_lower_bound(least_upper_bound(greatest_lower_bound(a, identity), greatest_lower_bound(identity, inverse(a))), least_upper_bound(least_upper_bound(greatest_lower_bound(a, identity), greatest_lower_bound(identity, inverse(a))), identity)) 5.85/6.04 = { by axiom 4 (symmetry_of_lub) } 5.85/6.04 greatest_lower_bound(least_upper_bound(greatest_lower_bound(a, identity), greatest_lower_bound(identity, inverse(a))), least_upper_bound(identity, least_upper_bound(greatest_lower_bound(a, identity), greatest_lower_bound(identity, inverse(a))))) 5.85/6.04 = { by axiom 4 (symmetry_of_lub) } 5.85/6.04 greatest_lower_bound(least_upper_bound(greatest_lower_bound(a, identity), greatest_lower_bound(identity, inverse(a))), least_upper_bound(identity, least_upper_bound(greatest_lower_bound(identity, inverse(a)), greatest_lower_bound(a, identity)))) 5.85/6.04 = { by axiom 13 (associativity_of_lub) } 5.85/6.04 greatest_lower_bound(least_upper_bound(greatest_lower_bound(a, identity), greatest_lower_bound(identity, inverse(a))), least_upper_bound(least_upper_bound(identity, greatest_lower_bound(identity, inverse(a))), greatest_lower_bound(a, identity))) 5.85/6.04 = { by axiom 6 (lub_absorbtion) } 5.85/6.04 greatest_lower_bound(least_upper_bound(greatest_lower_bound(a, identity), greatest_lower_bound(identity, inverse(a))), least_upper_bound(identity, greatest_lower_bound(a, identity))) 5.85/6.04 = { by axiom 8 (symmetry_of_glb) } 5.85/6.04 greatest_lower_bound(least_upper_bound(identity, greatest_lower_bound(a, identity)), least_upper_bound(greatest_lower_bound(a, identity), greatest_lower_bound(identity, inverse(a)))) 5.85/6.04 = { by axiom 8 (symmetry_of_glb) } 5.85/6.04 greatest_lower_bound(least_upper_bound(identity, greatest_lower_bound(identity, a)), least_upper_bound(greatest_lower_bound(a, identity), greatest_lower_bound(identity, inverse(a)))) 5.85/6.04 = { by axiom 6 (lub_absorbtion) } 5.85/6.04 greatest_lower_bound(identity, least_upper_bound(greatest_lower_bound(a, identity), greatest_lower_bound(identity, inverse(a)))) 5.85/6.04 = { by lemma 24 } 5.85/6.04 greatest_lower_bound(identity, multiply(least_upper_bound(a, identity), greatest_lower_bound(identity, inverse(a)))) 5.85/6.04 = { by axiom 8 (symmetry_of_glb) } 5.85/6.04 greatest_lower_bound(identity, multiply(least_upper_bound(a, identity), greatest_lower_bound(inverse(a), identity))) 5.85/6.04 = { by axiom 7 (monotony_glb1) } 5.85/6.05 greatest_lower_bound(identity, greatest_lower_bound(multiply(least_upper_bound(a, identity), inverse(a)), multiply(least_upper_bound(a, identity), identity))) 5.85/6.05 = { by lemma 17 } 5.85/6.05 greatest_lower_bound(identity, greatest_lower_bound(multiply(least_upper_bound(a, identity), inverse(a)), least_upper_bound(identity, multiply(a, identity)))) 5.85/6.05 = { by axiom 8 (symmetry_of_glb) } 5.85/6.05 greatest_lower_bound(identity, greatest_lower_bound(least_upper_bound(identity, multiply(a, identity)), multiply(least_upper_bound(a, identity), inverse(a)))) 5.85/6.05 = { by axiom 12 (associativity_of_glb) } 5.85/6.05 greatest_lower_bound(greatest_lower_bound(identity, least_upper_bound(identity, multiply(a, identity))), multiply(least_upper_bound(a, identity), inverse(a))) 5.85/6.05 = { by axiom 5 (glb_absorbtion) } 5.85/6.05 greatest_lower_bound(identity, multiply(least_upper_bound(a, identity), inverse(a))) 5.85/6.05 = { by axiom 9 (monotony_lub2) } 5.85/6.05 greatest_lower_bound(identity, least_upper_bound(multiply(a, inverse(a)), multiply(identity, inverse(a)))) 5.85/6.05 = { by lemma 21 } 5.85/6.05 greatest_lower_bound(identity, least_upper_bound(identity, multiply(identity, inverse(a)))) 5.85/6.05 = { by axiom 5 (glb_absorbtion) } 5.85/6.05 identity 5.85/6.05 % SZS output end Proof 5.85/6.05 5.85/6.05 RESULT: Unsatisfiable (the axioms are contradictory). 5.85/6.05 EOF