0.04/0.13 % Problem : theBenchmark.p : TPTP v0.0.0. Released v0.0.0. 0.04/0.14 % Command : twee %s --tstp --casc --quiet --explain-encoding --conditional-encoding if --smaller --drop-non-horn 0.14/0.35 % Computer : n004.cluster.edu 0.14/0.35 % Model : x86_64 x86_64 0.14/0.35 % CPU : Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz 0.14/0.35 % Memory : 8042.1875MB 0.14/0.35 % OS : Linux 3.10.0-693.el7.x86_64 0.14/0.35 % CPULimit : 180 0.14/0.35 % DateTime : Thu Aug 29 12:58:53 EDT 2019 0.14/0.35 % CPUTime : 6.11/6.25 % SZS status Unsatisfiable 6.11/6.25 6.11/6.25 % SZS output start Proof 6.11/6.25 Take the following subset of the input axioms: 6.20/6.36 fof(associativity, axiom, ![X, Y, Z]: multiply(multiply(X, Y), Z)=multiply(X, multiply(Y, Z))). 6.20/6.36 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)). 6.20/6.36 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)). 6.20/6.36 fof(glb_absorbtion, axiom, ![X, Y]: greatest_lower_bound(X, least_upper_bound(X, Y))=X). 6.20/6.36 fof(left_identity, axiom, ![X]: X=multiply(identity, X)). 6.20/6.36 fof(left_inverse, axiom, ![X]: multiply(inverse(X), X)=identity). 6.20/6.36 fof(lub_absorbtion, axiom, ![X, Y]: X=least_upper_bound(X, greatest_lower_bound(X, Y))). 6.20/6.36 fof(monotony_glb1, axiom, ![X, Y, Z]: multiply(X, greatest_lower_bound(Y, Z))=greatest_lower_bound(multiply(X, Y), multiply(X, Z))). 6.20/6.36 fof(monotony_glb2, axiom, ![X, Y, Z]: greatest_lower_bound(multiply(Y, X), multiply(Z, X))=multiply(greatest_lower_bound(Y, Z), X)). 6.20/6.36 fof(monotony_lub1, axiom, ![X, Y, Z]: least_upper_bound(multiply(X, Y), multiply(X, Z))=multiply(X, least_upper_bound(Y, Z))). 6.20/6.36 fof(monotony_lub2, axiom, ![X, Y, Z]: least_upper_bound(multiply(Y, X), multiply(Z, X))=multiply(least_upper_bound(Y, Z), X)). 6.20/6.36 fof(p11_1, hypothesis, identity=inverse(identity)). 6.20/6.36 fof(p11_2, hypothesis, ![X]: X=inverse(inverse(X))). 6.20/6.36 fof(p11_3, hypothesis, ![X, Y]: inverse(multiply(X, Y))=multiply(inverse(Y), inverse(X))). 6.20/6.36 fof(prove_p11, negated_conjecture, multiply(a, multiply(inverse(greatest_lower_bound(a, b)), b))!=least_upper_bound(a, b)). 6.20/6.36 fof(symmetry_of_glb, axiom, ![X, Y]: greatest_lower_bound(Y, X)=greatest_lower_bound(X, Y)). 6.20/6.36 fof(symmetry_of_lub, axiom, ![X, Y]: least_upper_bound(X, Y)=least_upper_bound(Y, X)). 6.20/6.36 6.20/6.36 Now clausify the problem and encode Horn clauses using encoding 3 of 6.20/6.36 http://www.cse.chalmers.se/~nicsma/papers/horn.pdf. 6.20/6.36 We repeatedly replace C & s=t => u=v by the two clauses: 6.20/6.36 fresh(y, y, x1...xn) = u 6.20/6.36 C => fresh(s, t, x1...xn) = v 6.20/6.36 where fresh is a fresh function symbol and x1..xn are the free 6.20/6.36 variables of u and v. 6.20/6.36 A predicate p(X) is encoded as p(X)=true (this is sound, because the 6.20/6.36 input problem has no model of domain size 1). 6.20/6.36 6.20/6.36 The encoding turns the above axioms into the following unit equations and goals: 6.20/6.36 6.20/6.36 Axiom 1 (left_inverse): multiply(inverse(X), X) = identity. 6.20/6.36 Axiom 2 (associativity): multiply(multiply(X, Y), Z) = multiply(X, multiply(Y, Z)). 6.20/6.36 Axiom 3 (left_identity): X = multiply(identity, X). 6.20/6.36 Axiom 4 (symmetry_of_lub): least_upper_bound(X, Y) = least_upper_bound(Y, X). 6.20/6.36 Axiom 5 (glb_absorbtion): greatest_lower_bound(X, least_upper_bound(X, Y)) = X. 6.20/6.36 Axiom 6 (lub_absorbtion): X = least_upper_bound(X, greatest_lower_bound(X, Y)). 6.20/6.36 Axiom 7 (monotony_glb1): multiply(X, greatest_lower_bound(Y, Z)) = greatest_lower_bound(multiply(X, Y), multiply(X, Z)). 6.20/6.36 Axiom 8 (symmetry_of_glb): greatest_lower_bound(X, Y) = greatest_lower_bound(Y, X). 6.20/6.36 Axiom 9 (monotony_lub2): least_upper_bound(multiply(X, Y), multiply(Z, Y)) = multiply(least_upper_bound(X, Z), Y). 6.20/6.36 Axiom 10 (monotony_glb2): greatest_lower_bound(multiply(X, Y), multiply(Z, Y)) = multiply(greatest_lower_bound(X, Z), Y). 6.20/6.36 Axiom 11 (monotony_lub1): least_upper_bound(multiply(X, Y), multiply(X, Z)) = multiply(X, least_upper_bound(Y, Z)). 6.20/6.36 Axiom 12 (associativity_of_glb): greatest_lower_bound(X, greatest_lower_bound(Y, Z)) = greatest_lower_bound(greatest_lower_bound(X, Y), Z). 6.20/6.36 Axiom 13 (associativity_of_lub): least_upper_bound(X, least_upper_bound(Y, Z)) = least_upper_bound(least_upper_bound(X, Y), Z). 6.20/6.36 Axiom 14 (p11_2): X = inverse(inverse(X)). 6.20/6.36 Axiom 15 (p11_3): inverse(multiply(X, Y)) = multiply(inverse(Y), inverse(X)). 6.20/6.36 Axiom 16 (p11_1): identity = inverse(identity). 6.20/6.36 6.20/6.36 Lemma 17: inverse(multiply(inverse(X), Y)) = multiply(inverse(Y), X). 6.20/6.36 Proof: 6.20/6.36 inverse(multiply(inverse(X), Y)) 6.20/6.36 = { by axiom 15 (p11_3) } 6.20/6.36 multiply(inverse(Y), inverse(inverse(X))) 6.20/6.36 = { by axiom 14 (p11_2) } 6.20/6.36 multiply(inverse(Y), X) 6.20/6.36 6.20/6.36 Lemma 18: multiply(X, identity) = X. 6.20/6.36 Proof: 6.20/6.36 multiply(X, identity) 6.20/6.36 = { by axiom 14 (p11_2) } 6.20/6.36 inverse(inverse(multiply(X, identity))) 6.20/6.36 = { by axiom 15 (p11_3) } 6.20/6.36 inverse(multiply(inverse(identity), inverse(X))) 6.20/6.36 = { by axiom 16 (p11_1) } 6.20/6.36 inverse(multiply(identity, inverse(X))) 6.20/6.36 = { by axiom 3 (left_identity) } 6.20/6.36 inverse(inverse(X)) 6.20/6.36 = { by axiom 14 (p11_2) } 6.20/6.36 X 6.20/6.36 6.20/6.36 Lemma 19: multiply(inverse(X), multiply(X, Y)) = Y. 6.20/6.36 Proof: 6.20/6.36 multiply(inverse(X), multiply(X, Y)) 6.20/6.36 = { by axiom 2 (associativity) } 6.20/6.36 multiply(multiply(inverse(X), X), Y) 6.20/6.36 = { by axiom 1 (left_inverse) } 6.20/6.36 multiply(identity, Y) 6.20/6.36 = { by axiom 3 (left_identity) } 6.20/6.36 Y 6.20/6.36 6.20/6.36 Lemma 20: greatest_lower_bound(Y, multiply(X, Y)) = multiply(greatest_lower_bound(X, identity), Y). 6.20/6.36 Proof: 6.20/6.36 greatest_lower_bound(Y, multiply(X, Y)) 6.20/6.36 = { by axiom 3 (left_identity) } 6.20/6.36 greatest_lower_bound(multiply(identity, Y), multiply(X, Y)) 6.20/6.36 = { by axiom 10 (monotony_glb2) } 6.20/6.36 multiply(greatest_lower_bound(identity, X), Y) 6.20/6.36 = { by axiom 8 (symmetry_of_glb) } 6.20/6.36 multiply(greatest_lower_bound(X, identity), Y) 6.20/6.36 6.20/6.36 Lemma 21: multiply(X, inverse(X)) = identity. 6.20/6.36 Proof: 6.20/6.36 multiply(X, inverse(X)) 6.20/6.36 = { by axiom 14 (p11_2) } 6.20/6.36 multiply(inverse(inverse(X)), inverse(X)) 6.20/6.36 = { by axiom 1 (left_inverse) } 6.20/6.36 identity 6.20/6.36 6.20/6.36 Lemma 22: least_upper_bound(identity, multiply(inverse(X), Y)) = multiply(inverse(X), least_upper_bound(X, Y)). 6.20/6.36 Proof: 6.20/6.36 least_upper_bound(identity, multiply(inverse(X), Y)) 6.20/6.36 = { by axiom 1 (left_inverse) } 6.20/6.36 least_upper_bound(multiply(inverse(X), X), multiply(inverse(X), Y)) 6.20/6.36 = { by axiom 11 (monotony_lub1) } 6.20/6.36 multiply(inverse(X), least_upper_bound(X, Y)) 6.20/6.36 6.20/6.36 Lemma 23: least_upper_bound(Y, multiply(X, Y)) = multiply(least_upper_bound(X, identity), Y). 6.20/6.36 Proof: 6.20/6.36 least_upper_bound(Y, multiply(X, Y)) 6.20/6.36 = { by axiom 3 (left_identity) } 6.20/6.36 least_upper_bound(multiply(identity, Y), multiply(X, Y)) 6.20/6.36 = { by axiom 9 (monotony_lub2) } 6.20/6.36 multiply(least_upper_bound(identity, X), Y) 6.20/6.36 = { by axiom 4 (symmetry_of_lub) } 6.20/6.36 multiply(least_upper_bound(X, identity), Y) 6.20/6.36 6.20/6.36 Lemma 24: multiply(inverse(X), greatest_lower_bound(X, identity)) = greatest_lower_bound(identity, inverse(X)). 6.20/6.36 Proof: 6.20/6.36 multiply(inverse(X), greatest_lower_bound(X, identity)) 6.20/6.36 = { by axiom 7 (monotony_glb1) } 6.20/6.36 greatest_lower_bound(multiply(inverse(X), X), multiply(inverse(X), identity)) 6.20/6.36 = { by axiom 1 (left_inverse) } 6.20/6.36 greatest_lower_bound(identity, multiply(inverse(X), identity)) 6.20/6.36 = { by lemma 20 } 6.20/6.36 multiply(greatest_lower_bound(inverse(X), identity), identity) 6.20/6.36 = { by lemma 18 } 6.20/6.36 greatest_lower_bound(inverse(X), identity) 6.20/6.36 = { by axiom 8 (symmetry_of_glb) } 6.20/6.36 greatest_lower_bound(identity, inverse(X)) 6.20/6.36 6.20/6.36 Lemma 25: multiply(least_upper_bound(identity, inverse(X)), greatest_lower_bound(X, identity)) = multiply(greatest_lower_bound(X, identity), least_upper_bound(identity, inverse(X))). 6.20/6.36 Proof: 6.20/6.36 multiply(least_upper_bound(identity, inverse(X)), greatest_lower_bound(X, identity)) 6.20/6.36 = { by axiom 4 (symmetry_of_lub) } 6.20/6.36 multiply(least_upper_bound(inverse(X), identity), greatest_lower_bound(X, identity)) 6.20/6.36 = { by lemma 23 } 6.20/6.36 least_upper_bound(greatest_lower_bound(X, identity), multiply(inverse(X), greatest_lower_bound(X, identity))) 6.20/6.36 = { by lemma 18 } 6.20/6.36 least_upper_bound(multiply(greatest_lower_bound(X, identity), identity), multiply(inverse(X), greatest_lower_bound(X, identity))) 6.20/6.36 = { by lemma 24 } 6.20/6.36 least_upper_bound(multiply(greatest_lower_bound(X, identity), identity), greatest_lower_bound(identity, inverse(X))) 6.20/6.36 = { by axiom 8 (symmetry_of_glb) } 6.20/6.36 least_upper_bound(multiply(greatest_lower_bound(X, identity), identity), greatest_lower_bound(inverse(X), identity)) 6.20/6.36 = { by lemma 21 } 6.20/6.36 least_upper_bound(multiply(greatest_lower_bound(X, identity), identity), greatest_lower_bound(inverse(X), multiply(X, inverse(X)))) 6.20/6.36 = { by lemma 20 } 6.20/6.36 least_upper_bound(multiply(greatest_lower_bound(X, identity), identity), multiply(greatest_lower_bound(X, identity), inverse(X))) 6.20/6.36 = { by axiom 11 (monotony_lub1) } 6.20/6.36 multiply(greatest_lower_bound(X, identity), least_upper_bound(identity, inverse(X))) 6.20/6.36 6.20/6.36 Lemma 26: 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))). 6.20/6.36 Proof: 6.20/6.36 least_upper_bound(greatest_lower_bound(X, identity), greatest_lower_bound(identity, inverse(X))) 6.20/6.36 = { by lemma 24 } 6.20/6.36 least_upper_bound(greatest_lower_bound(X, identity), multiply(inverse(X), greatest_lower_bound(X, identity))) 6.20/6.36 = { by axiom 4 (symmetry_of_lub) } 6.20/6.36 least_upper_bound(multiply(inverse(X), greatest_lower_bound(X, identity)), greatest_lower_bound(X, identity)) 6.20/6.36 = { by axiom 3 (left_identity) } 6.20/6.36 least_upper_bound(multiply(inverse(X), greatest_lower_bound(X, identity)), multiply(identity, greatest_lower_bound(X, identity))) 6.20/6.36 = { by lemma 21 } 6.20/6.36 least_upper_bound(multiply(inverse(X), greatest_lower_bound(X, identity)), multiply(multiply(X, inverse(X)), greatest_lower_bound(X, identity))) 6.20/6.36 = { by axiom 2 (associativity) } 6.20/6.36 least_upper_bound(multiply(inverse(X), greatest_lower_bound(X, identity)), multiply(X, multiply(inverse(X), greatest_lower_bound(X, identity)))) 6.20/6.36 = { by lemma 23 } 6.20/6.36 multiply(least_upper_bound(X, identity), multiply(inverse(X), greatest_lower_bound(X, identity))) 6.20/6.36 = { by lemma 24 } 6.30/6.48 multiply(least_upper_bound(X, identity), greatest_lower_bound(identity, inverse(X))) 6.30/6.48 6.30/6.48 Goal 1 (prove_p11): multiply(a, multiply(inverse(greatest_lower_bound(a, b)), b)) = least_upper_bound(a, b). 6.30/6.48 Proof: 6.30/6.48 multiply(a, multiply(inverse(greatest_lower_bound(a, b)), b)) 6.30/6.48 = { by axiom 14 (p11_2) } 6.30/6.48 multiply(inverse(inverse(a)), multiply(inverse(greatest_lower_bound(a, b)), b)) 6.30/6.48 = { by lemma 17 } 6.30/6.48 multiply(inverse(inverse(a)), inverse(multiply(inverse(b), greatest_lower_bound(a, b)))) 6.30/6.48 = { by axiom 8 (symmetry_of_glb) } 6.30/6.48 multiply(inverse(inverse(a)), inverse(multiply(inverse(b), greatest_lower_bound(b, a)))) 6.30/6.48 = { by axiom 7 (monotony_glb1) } 6.30/6.48 multiply(inverse(inverse(a)), inverse(greatest_lower_bound(multiply(inverse(b), b), multiply(inverse(b), a)))) 6.30/6.48 = { by axiom 1 (left_inverse) } 6.30/6.48 multiply(inverse(inverse(a)), inverse(greatest_lower_bound(identity, multiply(inverse(b), a)))) 6.30/6.48 = { by axiom 14 (p11_2) } 6.30/6.48 multiply(inverse(inverse(a)), inverse(greatest_lower_bound(identity, multiply(inverse(b), inverse(inverse(a)))))) 6.30/6.48 = { by axiom 15 (p11_3) } 6.30/6.48 inverse(multiply(greatest_lower_bound(identity, multiply(inverse(b), inverse(inverse(a)))), inverse(a))) 6.30/6.48 = { by axiom 8 (symmetry_of_glb) } 6.30/6.48 inverse(multiply(greatest_lower_bound(multiply(inverse(b), inverse(inverse(a))), identity), inverse(a))) 6.30/6.48 = { by axiom 10 (monotony_glb2) } 6.30/6.48 inverse(greatest_lower_bound(multiply(multiply(inverse(b), inverse(inverse(a))), inverse(a)), multiply(identity, inverse(a)))) 6.30/6.48 = { by axiom 2 (associativity) } 6.30/6.48 inverse(greatest_lower_bound(multiply(inverse(b), multiply(inverse(inverse(a)), inverse(a))), multiply(identity, inverse(a)))) 6.30/6.48 = { by axiom 1 (left_inverse) } 6.30/6.48 inverse(greatest_lower_bound(multiply(inverse(b), identity), multiply(identity, inverse(a)))) 6.30/6.48 = { by lemma 18 } 6.30/6.48 inverse(greatest_lower_bound(inverse(b), multiply(identity, inverse(a)))) 6.30/6.48 = { by axiom 3 (left_identity) } 6.30/6.48 inverse(greatest_lower_bound(inverse(b), inverse(a))) 6.30/6.48 = { by axiom 8 (symmetry_of_glb) } 6.30/6.48 inverse(greatest_lower_bound(inverse(a), inverse(b))) 6.30/6.48 = { by lemma 19 } 6.30/6.48 inverse(greatest_lower_bound(multiply(inverse(b), multiply(b, inverse(a))), inverse(b))) 6.30/6.48 = { by lemma 18 } 6.30/6.48 inverse(greatest_lower_bound(multiply(inverse(b), multiply(b, inverse(a))), multiply(inverse(b), identity))) 6.30/6.48 = { by axiom 7 (monotony_glb1) } 6.30/6.48 inverse(multiply(inverse(b), greatest_lower_bound(multiply(b, inverse(a)), identity))) 6.30/6.48 = { by axiom 8 (symmetry_of_glb) } 6.30/6.48 inverse(multiply(inverse(b), greatest_lower_bound(identity, multiply(b, inverse(a))))) 6.30/6.48 = { by lemma 17 } 6.30/6.48 multiply(inverse(greatest_lower_bound(identity, multiply(b, inverse(a)))), b) 6.30/6.48 = { by axiom 8 (symmetry_of_glb) } 6.30/6.48 multiply(inverse(greatest_lower_bound(multiply(b, inverse(a)), identity)), b) 6.30/6.48 = { by lemma 18 } 6.30/6.48 multiply(inverse(multiply(greatest_lower_bound(multiply(b, inverse(a)), identity), identity)), b) 6.30/6.48 = { by lemma 20 } 6.30/6.48 multiply(inverse(greatest_lower_bound(identity, multiply(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by lemma 21 } 6.30/6.48 multiply(inverse(greatest_lower_bound(multiply(multiply(b, inverse(a)), inverse(multiply(b, inverse(a)))), multiply(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by axiom 7 (monotony_glb1) } 6.30/6.48 multiply(inverse(multiply(multiply(b, inverse(a)), greatest_lower_bound(inverse(multiply(b, inverse(a))), identity))), b) 6.30/6.48 = { by axiom 8 (symmetry_of_glb) } 6.30/6.48 multiply(inverse(multiply(multiply(b, inverse(a)), greatest_lower_bound(identity, inverse(multiply(b, inverse(a)))))), b) 6.30/6.48 = { by lemma 19 } 6.30/6.48 multiply(inverse(multiply(inverse(least_upper_bound(multiply(b, inverse(a)), identity)), multiply(least_upper_bound(multiply(b, inverse(a)), identity), multiply(multiply(b, inverse(a)), greatest_lower_bound(identity, inverse(multiply(b, inverse(a)))))))), b) 6.30/6.48 = { by lemma 17 } 6.30/6.48 multiply(multiply(inverse(multiply(least_upper_bound(multiply(b, inverse(a)), identity), multiply(multiply(b, inverse(a)), greatest_lower_bound(identity, inverse(multiply(b, inverse(a))))))), least_upper_bound(multiply(b, inverse(a)), identity)), b) 6.30/6.48 = { by lemma 23 } 6.30/6.48 multiply(multiply(inverse(least_upper_bound(multiply(multiply(b, inverse(a)), greatest_lower_bound(identity, inverse(multiply(b, inverse(a))))), multiply(multiply(b, inverse(a)), multiply(multiply(b, inverse(a)), greatest_lower_bound(identity, inverse(multiply(b, inverse(a)))))))), least_upper_bound(multiply(b, inverse(a)), identity)), b) 6.30/6.48 = { by axiom 11 (monotony_lub1) } 6.30/6.48 multiply(multiply(inverse(multiply(multiply(b, inverse(a)), least_upper_bound(greatest_lower_bound(identity, inverse(multiply(b, inverse(a)))), multiply(multiply(b, inverse(a)), greatest_lower_bound(identity, inverse(multiply(b, inverse(a)))))))), least_upper_bound(multiply(b, inverse(a)), identity)), b) 6.30/6.48 = { by lemma 23 } 6.30/6.48 multiply(multiply(inverse(multiply(multiply(b, inverse(a)), multiply(least_upper_bound(multiply(b, inverse(a)), identity), greatest_lower_bound(identity, inverse(multiply(b, inverse(a))))))), least_upper_bound(multiply(b, inverse(a)), identity)), b) 6.30/6.48 = { by axiom 15 (p11_3) } 6.30/6.48 multiply(multiply(multiply(inverse(multiply(least_upper_bound(multiply(b, inverse(a)), identity), greatest_lower_bound(identity, inverse(multiply(b, inverse(a)))))), inverse(multiply(b, inverse(a)))), least_upper_bound(multiply(b, inverse(a)), identity)), b) 6.30/6.48 = { by axiom 2 (associativity) } 6.30/6.48 multiply(multiply(inverse(multiply(least_upper_bound(multiply(b, inverse(a)), identity), greatest_lower_bound(identity, inverse(multiply(b, inverse(a)))))), multiply(inverse(multiply(b, inverse(a))), least_upper_bound(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by lemma 26 } 6.30/6.48 multiply(multiply(inverse(least_upper_bound(greatest_lower_bound(multiply(b, inverse(a)), identity), greatest_lower_bound(identity, inverse(multiply(b, inverse(a)))))), multiply(inverse(multiply(b, inverse(a))), least_upper_bound(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by axiom 5 (glb_absorbtion) } 6.30/6.48 multiply(multiply(inverse(greatest_lower_bound(least_upper_bound(greatest_lower_bound(multiply(b, inverse(a)), identity), greatest_lower_bound(identity, inverse(multiply(b, inverse(a))))), least_upper_bound(least_upper_bound(greatest_lower_bound(multiply(b, inverse(a)), identity), greatest_lower_bound(identity, inverse(multiply(b, inverse(a))))), identity))), multiply(inverse(multiply(b, inverse(a))), least_upper_bound(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by axiom 4 (symmetry_of_lub) } 6.30/6.48 multiply(multiply(inverse(greatest_lower_bound(least_upper_bound(greatest_lower_bound(multiply(b, inverse(a)), identity), greatest_lower_bound(identity, inverse(multiply(b, inverse(a))))), least_upper_bound(identity, least_upper_bound(greatest_lower_bound(multiply(b, inverse(a)), identity), greatest_lower_bound(identity, inverse(multiply(b, inverse(a)))))))), multiply(inverse(multiply(b, inverse(a))), least_upper_bound(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by axiom 4 (symmetry_of_lub) } 6.30/6.48 multiply(multiply(inverse(greatest_lower_bound(least_upper_bound(greatest_lower_bound(multiply(b, inverse(a)), identity), greatest_lower_bound(identity, inverse(multiply(b, inverse(a))))), least_upper_bound(identity, least_upper_bound(greatest_lower_bound(identity, inverse(multiply(b, inverse(a)))), greatest_lower_bound(multiply(b, inverse(a)), identity))))), multiply(inverse(multiply(b, inverse(a))), least_upper_bound(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by axiom 13 (associativity_of_lub) } 6.30/6.48 multiply(multiply(inverse(greatest_lower_bound(least_upper_bound(greatest_lower_bound(multiply(b, inverse(a)), identity), greatest_lower_bound(identity, inverse(multiply(b, inverse(a))))), least_upper_bound(least_upper_bound(identity, greatest_lower_bound(identity, inverse(multiply(b, inverse(a))))), greatest_lower_bound(multiply(b, inverse(a)), identity)))), multiply(inverse(multiply(b, inverse(a))), least_upper_bound(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by axiom 6 (lub_absorbtion) } 6.30/6.48 multiply(multiply(inverse(greatest_lower_bound(least_upper_bound(greatest_lower_bound(multiply(b, inverse(a)), identity), greatest_lower_bound(identity, inverse(multiply(b, inverse(a))))), least_upper_bound(identity, greatest_lower_bound(multiply(b, inverse(a)), identity)))), multiply(inverse(multiply(b, inverse(a))), least_upper_bound(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by axiom 8 (symmetry_of_glb) } 6.30/6.48 multiply(multiply(inverse(greatest_lower_bound(least_upper_bound(identity, greatest_lower_bound(multiply(b, inverse(a)), identity)), least_upper_bound(greatest_lower_bound(multiply(b, inverse(a)), identity), greatest_lower_bound(identity, inverse(multiply(b, inverse(a))))))), multiply(inverse(multiply(b, inverse(a))), least_upper_bound(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by axiom 8 (symmetry_of_glb) } 6.30/6.48 multiply(multiply(inverse(greatest_lower_bound(least_upper_bound(identity, greatest_lower_bound(identity, multiply(b, inverse(a)))), least_upper_bound(greatest_lower_bound(multiply(b, inverse(a)), identity), greatest_lower_bound(identity, inverse(multiply(b, inverse(a))))))), multiply(inverse(multiply(b, inverse(a))), least_upper_bound(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by axiom 6 (lub_absorbtion) } 6.30/6.48 multiply(multiply(inverse(greatest_lower_bound(identity, least_upper_bound(greatest_lower_bound(multiply(b, inverse(a)), identity), greatest_lower_bound(identity, inverse(multiply(b, inverse(a))))))), multiply(inverse(multiply(b, inverse(a))), least_upper_bound(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by lemma 26 } 6.30/6.48 multiply(multiply(inverse(greatest_lower_bound(identity, multiply(least_upper_bound(multiply(b, inverse(a)), identity), greatest_lower_bound(identity, inverse(multiply(b, inverse(a))))))), multiply(inverse(multiply(b, inverse(a))), least_upper_bound(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by axiom 8 (symmetry_of_glb) } 6.30/6.48 multiply(multiply(inverse(greatest_lower_bound(identity, multiply(least_upper_bound(multiply(b, inverse(a)), identity), greatest_lower_bound(inverse(multiply(b, inverse(a))), identity)))), multiply(inverse(multiply(b, inverse(a))), least_upper_bound(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by axiom 7 (monotony_glb1) } 6.30/6.48 multiply(multiply(inverse(greatest_lower_bound(identity, greatest_lower_bound(multiply(least_upper_bound(multiply(b, inverse(a)), identity), inverse(multiply(b, inverse(a)))), multiply(least_upper_bound(multiply(b, inverse(a)), identity), identity)))), multiply(inverse(multiply(b, inverse(a))), least_upper_bound(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by lemma 23 } 6.30/6.48 multiply(multiply(inverse(greatest_lower_bound(identity, greatest_lower_bound(multiply(least_upper_bound(multiply(b, inverse(a)), identity), inverse(multiply(b, inverse(a)))), least_upper_bound(identity, multiply(multiply(b, inverse(a)), identity))))), multiply(inverse(multiply(b, inverse(a))), least_upper_bound(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by axiom 8 (symmetry_of_glb) } 6.30/6.48 multiply(multiply(inverse(greatest_lower_bound(identity, greatest_lower_bound(least_upper_bound(identity, multiply(multiply(b, inverse(a)), identity)), multiply(least_upper_bound(multiply(b, inverse(a)), identity), inverse(multiply(b, inverse(a))))))), multiply(inverse(multiply(b, inverse(a))), least_upper_bound(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by axiom 12 (associativity_of_glb) } 6.30/6.48 multiply(multiply(inverse(greatest_lower_bound(greatest_lower_bound(identity, least_upper_bound(identity, multiply(multiply(b, inverse(a)), identity))), multiply(least_upper_bound(multiply(b, inverse(a)), identity), inverse(multiply(b, inverse(a)))))), multiply(inverse(multiply(b, inverse(a))), least_upper_bound(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by axiom 5 (glb_absorbtion) } 6.30/6.48 multiply(multiply(inverse(greatest_lower_bound(identity, multiply(least_upper_bound(multiply(b, inverse(a)), identity), inverse(multiply(b, inverse(a)))))), multiply(inverse(multiply(b, inverse(a))), least_upper_bound(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by axiom 9 (monotony_lub2) } 6.30/6.48 multiply(multiply(inverse(greatest_lower_bound(identity, least_upper_bound(multiply(multiply(b, inverse(a)), inverse(multiply(b, inverse(a)))), multiply(identity, inverse(multiply(b, inverse(a))))))), multiply(inverse(multiply(b, inverse(a))), least_upper_bound(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by lemma 21 } 6.30/6.48 multiply(multiply(inverse(greatest_lower_bound(identity, least_upper_bound(identity, multiply(identity, inverse(multiply(b, inverse(a))))))), multiply(inverse(multiply(b, inverse(a))), least_upper_bound(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by axiom 5 (glb_absorbtion) } 6.30/6.48 multiply(multiply(inverse(identity), multiply(inverse(multiply(b, inverse(a))), least_upper_bound(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by lemma 22 } 6.30/6.48 multiply(multiply(inverse(identity), least_upper_bound(identity, multiply(inverse(multiply(b, inverse(a))), identity))), b) 6.30/6.48 = { by lemma 23 } 6.30/6.48 multiply(multiply(inverse(identity), multiply(least_upper_bound(inverse(multiply(b, inverse(a))), identity), identity)), b) 6.30/6.48 = { by lemma 18 } 6.30/6.48 multiply(multiply(inverse(identity), least_upper_bound(inverse(multiply(b, inverse(a))), identity)), b) 6.30/6.48 = { by axiom 4 (symmetry_of_lub) } 6.30/6.48 multiply(multiply(inverse(identity), least_upper_bound(identity, inverse(multiply(b, inverse(a))))), b) 6.30/6.48 = { by lemma 22 } 6.30/6.48 multiply(least_upper_bound(identity, multiply(inverse(identity), inverse(multiply(b, inverse(a))))), b) 6.30/6.48 = { by axiom 15 (p11_3) } 6.30/6.48 multiply(least_upper_bound(identity, inverse(multiply(multiply(b, inverse(a)), identity))), b) 6.30/6.48 = { by lemma 18 } 6.30/6.48 multiply(least_upper_bound(identity, inverse(multiply(b, inverse(a)))), b) 6.30/6.48 = { by axiom 4 (symmetry_of_lub) } 6.30/6.48 multiply(least_upper_bound(inverse(multiply(b, inverse(a))), identity), b) 6.30/6.48 = { by axiom 14 (p11_2) } 6.30/6.48 multiply(least_upper_bound(inverse(multiply(b, inverse(a))), identity), inverse(inverse(b))) 6.30/6.48 = { by axiom 9 (monotony_lub2) } 6.30/6.48 least_upper_bound(multiply(inverse(multiply(b, inverse(a))), inverse(inverse(b))), multiply(identity, inverse(inverse(b)))) 6.30/6.48 = { by axiom 15 (p11_3) } 6.30/6.48 least_upper_bound(inverse(multiply(inverse(b), multiply(b, inverse(a)))), multiply(identity, inverse(inverse(b)))) 6.30/6.48 = { by axiom 4 (symmetry_of_lub) } 6.30/6.48 least_upper_bound(multiply(identity, inverse(inverse(b))), inverse(multiply(inverse(b), multiply(b, inverse(a))))) 6.30/6.48 = { by axiom 14 (p11_2) } 6.30/6.48 least_upper_bound(multiply(identity, b), inverse(multiply(inverse(b), multiply(b, inverse(a))))) 6.30/6.48 = { by lemma 19 } 6.30/6.48 least_upper_bound(multiply(identity, b), inverse(inverse(a))) 6.30/6.48 = { by axiom 4 (symmetry_of_lub) } 6.30/6.48 least_upper_bound(inverse(inverse(a)), multiply(identity, b)) 6.30/6.48 = { by axiom 3 (left_identity) } 6.30/6.48 least_upper_bound(inverse(inverse(a)), b) 6.30/6.48 = { by axiom 4 (symmetry_of_lub) } 6.30/6.48 least_upper_bound(b, inverse(inverse(a))) 6.30/6.48 = { by axiom 14 (p11_2) } 6.30/6.48 least_upper_bound(b, a) 6.30/6.48 = { by axiom 4 (symmetry_of_lub) } 6.30/6.48 least_upper_bound(a, b) 6.30/6.48 % SZS output end Proof 6.30/6.48 6.30/6.48 RESULT: Unsatisfiable (the axioms are contradictory). 6.30/6.48 EOF