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 0.12/0.33 % Computer : n014.cluster.edu 0.12/0.33 % Model : x86_64 x86_64 0.12/0.33 % CPU : Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz 0.12/0.33 % Memory : 8042.1875MB 0.12/0.33 % OS : Linux 3.10.0-693.el7.x86_64 0.12/0.33 % CPULimit : 180 0.12/0.33 % DateTime : Thu Aug 29 11:16:39 EDT 2019 0.12/0.34 % CPUTime : 119.57/119.80 % SZS status Unsatisfiable 119.57/119.80 119.57/119.80 % SZS output start Proof 119.57/119.80 Take the following subset of the input axioms: 119.57/119.81 fof(associativity, axiom, ![X, Y, Z]: multiply(multiply(X, Y), Z)=multiply(X, multiply(Y, Z))). 119.57/119.81 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)). 119.57/119.81 fof(glb_absorbtion, axiom, ![X, Y]: greatest_lower_bound(X, least_upper_bound(X, Y))=X). 119.57/119.81 fof(idempotence_of_lub, axiom, ![X]: least_upper_bound(X, X)=X). 119.57/119.81 fof(left_identity, axiom, ![X]: X=multiply(identity, X)). 119.57/119.81 fof(left_inverse, axiom, ![X]: multiply(inverse(X), X)=identity). 119.57/119.81 fof(monotony_glb1, axiom, ![X, Y, Z]: multiply(X, greatest_lower_bound(Y, Z))=greatest_lower_bound(multiply(X, Y), multiply(X, Z))). 119.57/119.81 fof(monotony_lub1, axiom, ![X, Y, Z]: least_upper_bound(multiply(X, Y), multiply(X, Z))=multiply(X, least_upper_bound(Y, Z))). 119.57/119.81 fof(monotony_lub2, axiom, ![X, Y, Z]: least_upper_bound(multiply(Y, X), multiply(Z, X))=multiply(least_upper_bound(Y, Z), X)). 119.57/119.81 fof(prove_p22a, negated_conjecture, multiply(least_upper_bound(a, identity), least_upper_bound(b, identity))!=least_upper_bound(least_upper_bound(multiply(a, b), identity), multiply(least_upper_bound(a, identity), least_upper_bound(b, identity)))). 119.57/119.81 fof(symmetry_of_glb, axiom, ![X, Y]: greatest_lower_bound(Y, X)=greatest_lower_bound(X, Y)). 119.57/119.81 fof(symmetry_of_lub, axiom, ![X, Y]: least_upper_bound(X, Y)=least_upper_bound(Y, X)). 119.57/119.81 119.57/119.81 Now clausify the problem and encode Horn clauses using encoding 3 of 119.57/119.81 http://www.cse.chalmers.se/~nicsma/papers/horn.pdf. 119.57/119.81 We repeatedly replace C & s=t => u=v by the two clauses: 119.57/119.81 fresh(y, y, x1...xn) = u 119.57/119.81 C => fresh(s, t, x1...xn) = v 119.57/119.81 where fresh is a fresh function symbol and x1..xn are the free 119.57/119.81 variables of u and v. 119.57/119.81 A predicate p(X) is encoded as p(X)=true (this is sound, because the 119.57/119.81 input problem has no model of domain size 1). 119.57/119.81 119.57/119.81 The encoding turns the above axioms into the following unit equations and goals: 119.57/119.81 119.57/119.82 Axiom 1 (left_inverse): multiply(inverse(X), X) = identity. 119.57/119.82 Axiom 2 (associativity): multiply(multiply(X, Y), Z) = multiply(X, multiply(Y, Z)). 119.57/119.82 Axiom 3 (left_identity): X = multiply(identity, X). 119.57/119.82 Axiom 4 (symmetry_of_lub): least_upper_bound(X, Y) = least_upper_bound(Y, X). 119.57/119.82 Axiom 5 (glb_absorbtion): greatest_lower_bound(X, least_upper_bound(X, Y)) = X. 119.57/119.82 Axiom 6 (monotony_glb1): multiply(X, greatest_lower_bound(Y, Z)) = greatest_lower_bound(multiply(X, Y), multiply(X, Z)). 119.57/119.82 Axiom 7 (symmetry_of_glb): greatest_lower_bound(X, Y) = greatest_lower_bound(Y, X). 119.57/119.82 Axiom 8 (idempotence_of_lub): least_upper_bound(X, X) = X. 119.57/119.82 Axiom 9 (monotony_lub2): least_upper_bound(multiply(X, Y), multiply(Z, Y)) = multiply(least_upper_bound(X, Z), Y). 119.57/119.82 Axiom 10 (monotony_lub1): least_upper_bound(multiply(X, Y), multiply(X, Z)) = multiply(X, least_upper_bound(Y, Z)). 119.57/119.82 Axiom 11 (associativity_of_lub): least_upper_bound(X, least_upper_bound(Y, Z)) = least_upper_bound(least_upper_bound(X, Y), Z). 119.57/119.82 119.57/119.82 Lemma 12: least_upper_bound(X, least_upper_bound(Y, Z)) = least_upper_bound(Y, least_upper_bound(X, Z)). 119.57/119.82 Proof: 119.57/119.82 least_upper_bound(X, least_upper_bound(Y, Z)) 119.57/119.82 = { by axiom 11 (associativity_of_lub) } 119.57/119.82 least_upper_bound(least_upper_bound(X, Y), Z) 119.57/119.82 = { by axiom 4 (symmetry_of_lub) } 119.57/119.82 least_upper_bound(least_upper_bound(Y, X), Z) 119.57/119.82 = { by axiom 11 (associativity_of_lub) } 119.57/119.82 least_upper_bound(Y, least_upper_bound(X, Z)) 119.57/119.82 119.57/119.82 Lemma 13: multiply(inverse(X), multiply(X, Y)) = Y. 119.57/119.82 Proof: 119.57/119.82 multiply(inverse(X), multiply(X, Y)) 119.57/119.82 = { by axiom 2 (associativity) } 119.57/119.82 multiply(multiply(inverse(X), X), Y) 119.57/119.82 = { by axiom 1 (left_inverse) } 119.57/119.82 multiply(identity, Y) 119.57/119.82 = { by axiom 3 (left_identity) } 119.57/119.82 Y 119.57/119.82 119.57/119.82 Lemma 14: multiply(inverse(inverse(X)), Y) = multiply(X, Y). 119.57/119.82 Proof: 119.57/119.82 multiply(inverse(inverse(X)), Y) 119.57/119.82 = { by lemma 13 } 119.57/119.82 multiply(inverse(inverse(X)), multiply(inverse(X), multiply(X, Y))) 119.57/119.82 = { by lemma 13 } 119.57/119.82 multiply(X, Y) 119.57/119.82 119.57/119.82 Lemma 15: multiply(inverse(inverse(X)), identity) = X. 119.57/119.82 Proof: 119.57/119.82 multiply(inverse(inverse(X)), identity) 119.57/119.82 = { by axiom 1 (left_inverse) } 119.57/119.82 multiply(inverse(inverse(X)), multiply(inverse(X), X)) 119.57/119.82 = { by lemma 13 } 119.57/119.82 X 119.57/119.82 119.57/119.82 Lemma 16: multiply(X, identity) = X. 119.57/119.82 Proof: 119.57/119.82 multiply(X, identity) 119.57/119.82 = { by lemma 14 } 119.57/119.82 multiply(inverse(inverse(X)), identity) 119.57/119.82 = { by lemma 15 } 119.57/119.82 X 119.57/119.82 119.57/119.82 Lemma 17: inverse(inverse(X)) = X. 119.57/119.82 Proof: 119.57/119.82 inverse(inverse(X)) 119.57/119.82 = { by lemma 16 } 119.57/119.82 multiply(inverse(inverse(X)), identity) 119.57/119.82 = { by lemma 15 } 119.57/119.82 X 119.57/119.82 119.57/119.82 Lemma 18: multiply(inverse(X), least_upper_bound(Z, multiply(X, Y))) = least_upper_bound(Y, multiply(inverse(X), Z)). 119.57/119.82 Proof: 119.57/119.82 multiply(inverse(X), least_upper_bound(Z, multiply(X, Y))) 119.57/119.82 = { by axiom 4 (symmetry_of_lub) } 119.57/119.82 multiply(inverse(X), least_upper_bound(multiply(X, Y), Z)) 119.57/119.82 = { by axiom 10 (monotony_lub1) } 119.57/119.82 least_upper_bound(multiply(inverse(X), multiply(X, Y)), multiply(inverse(X), Z)) 119.57/119.82 = { by lemma 13 } 119.57/119.82 least_upper_bound(Y, multiply(inverse(X), Z)) 119.57/119.82 119.57/119.82 Lemma 19: least_upper_bound(Y, multiply(X, Y)) = multiply(least_upper_bound(X, identity), Y). 119.57/119.82 Proof: 119.57/119.82 least_upper_bound(Y, multiply(X, Y)) 119.57/119.82 = { by axiom 3 (left_identity) } 119.57/119.82 least_upper_bound(multiply(identity, Y), multiply(X, Y)) 119.57/119.82 = { by axiom 9 (monotony_lub2) } 119.57/119.82 multiply(least_upper_bound(identity, X), Y) 119.57/119.82 = { by axiom 4 (symmetry_of_lub) } 119.57/119.82 multiply(least_upper_bound(X, identity), Y) 119.57/119.82 119.57/119.82 Lemma 20: multiply(inverse(X), least_upper_bound(X, identity)) = least_upper_bound(identity, inverse(X)). 119.57/119.82 Proof: 119.57/119.82 multiply(inverse(X), least_upper_bound(X, identity)) 119.57/119.82 = { by axiom 10 (monotony_lub1) } 119.57/119.82 least_upper_bound(multiply(inverse(X), X), multiply(inverse(X), identity)) 119.57/119.82 = { by axiom 1 (left_inverse) } 119.57/119.82 least_upper_bound(identity, multiply(inverse(X), identity)) 119.57/119.82 = { by lemma 19 } 119.57/119.82 multiply(least_upper_bound(inverse(X), identity), identity) 119.57/119.82 = { by lemma 16 } 119.57/119.82 least_upper_bound(inverse(X), identity) 119.57/119.82 = { by axiom 4 (symmetry_of_lub) } 119.57/119.82 least_upper_bound(identity, inverse(X)) 119.57/119.82 119.57/119.82 Lemma 21: least_upper_bound(X, least_upper_bound(Y, Z)) = least_upper_bound(Z, least_upper_bound(X, Y)). 119.57/119.82 Proof: 119.57/119.82 least_upper_bound(X, least_upper_bound(Y, Z)) 119.57/119.82 = { by axiom 11 (associativity_of_lub) } 119.57/119.82 least_upper_bound(least_upper_bound(X, Y), Z) 119.57/119.82 = { by axiom 4 (symmetry_of_lub) } 119.57/119.82 least_upper_bound(Z, least_upper_bound(X, Y)) 119.57/119.82 119.57/119.82 Lemma 22: least_upper_bound(Z, multiply(least_upper_bound(X, identity), Y)) = least_upper_bound(Y, least_upper_bound(multiply(X, Y), Z)). 119.57/119.82 Proof: 119.57/119.82 least_upper_bound(Z, multiply(least_upper_bound(X, identity), Y)) 119.57/119.82 = { by lemma 19 } 119.57/119.82 least_upper_bound(Z, least_upper_bound(Y, multiply(X, Y))) 119.57/119.82 = { by lemma 21 } 119.57/119.82 least_upper_bound(multiply(X, Y), least_upper_bound(Z, Y)) 119.57/119.82 = { by lemma 21 } 119.57/119.82 least_upper_bound(Y, least_upper_bound(multiply(X, Y), Z)) 119.57/119.82 119.57/119.82 Lemma 23: least_upper_bound(identity, inverse(least_upper_bound(X, identity))) = identity. 119.57/119.82 Proof: 119.57/119.82 least_upper_bound(identity, inverse(least_upper_bound(X, identity))) 119.57/119.82 = { by axiom 4 (symmetry_of_lub) } 119.57/119.82 least_upper_bound(identity, inverse(least_upper_bound(identity, X))) 119.57/119.82 = { by lemma 20 } 119.57/119.82 multiply(inverse(least_upper_bound(identity, X)), least_upper_bound(least_upper_bound(identity, X), identity)) 119.57/119.82 = { by axiom 4 (symmetry_of_lub) } 119.57/119.82 multiply(inverse(least_upper_bound(identity, X)), least_upper_bound(identity, least_upper_bound(identity, X))) 119.57/119.82 = { by lemma 26 } 119.57/119.82 multiply(inverse(least_upper_bound(identity, X)), least_upper_bound(identity, X)) 119.57/119.82 = { by axiom 1 (left_inverse) } 119.57/119.82 identity 119.57/119.82 119.57/119.82 Lemma 24: multiply(least_upper_bound(multiply(X, inverse(Z)), Y), Z) = least_upper_bound(X, multiply(Y, Z)). 119.57/119.82 Proof: 119.57/119.82 multiply(least_upper_bound(multiply(X, inverse(Z)), Y), Z) 119.57/119.82 = { by axiom 4 (symmetry_of_lub) } 119.57/119.82 multiply(least_upper_bound(Y, multiply(X, inverse(Z))), Z) 119.57/119.82 = { by axiom 4 (symmetry_of_lub) } 119.57/119.82 multiply(least_upper_bound(multiply(X, inverse(Z)), Y), Z) 119.57/119.82 = { by axiom 9 (monotony_lub2) } 119.57/119.82 least_upper_bound(multiply(multiply(X, inverse(Z)), Z), multiply(Y, Z)) 119.57/119.82 = { by axiom 2 (associativity) } 119.57/119.82 least_upper_bound(multiply(X, multiply(inverse(Z), Z)), multiply(Y, Z)) 119.57/119.82 = { by axiom 1 (left_inverse) } 119.57/119.82 least_upper_bound(multiply(X, identity), multiply(Y, Z)) 119.57/119.82 = { by lemma 16 } 119.57/119.82 least_upper_bound(X, multiply(Y, Z)) 119.57/119.82 119.57/119.82 Lemma 25: least_upper_bound(Y, least_upper_bound(Z, multiply(X, least_upper_bound(Y, Z)))) = multiply(least_upper_bound(X, identity), least_upper_bound(Y, Z)). 119.57/119.82 Proof: 119.57/119.82 least_upper_bound(Y, least_upper_bound(Z, multiply(X, least_upper_bound(Y, Z)))) 119.57/119.82 = { by axiom 11 (associativity_of_lub) } 119.57/119.82 least_upper_bound(least_upper_bound(Y, Z), multiply(X, least_upper_bound(Y, Z))) 119.57/119.82 = { by lemma 19 } 119.57/119.83 multiply(least_upper_bound(X, identity), least_upper_bound(Y, Z)) 119.57/119.83 119.57/119.83 Lemma 26: least_upper_bound(X, least_upper_bound(X, Y)) = least_upper_bound(X, Y). 119.57/119.83 Proof: 119.57/119.83 least_upper_bound(X, least_upper_bound(X, Y)) 119.57/119.83 = { by axiom 3 (left_identity) } 119.57/119.83 least_upper_bound(X, least_upper_bound(multiply(identity, X), Y)) 119.57/119.83 = { by axiom 8 (idempotence_of_lub) } 119.57/119.83 least_upper_bound(X, least_upper_bound(multiply(least_upper_bound(identity, identity), X), Y)) 119.57/119.83 = { by lemma 22 } 119.57/119.83 least_upper_bound(Y, multiply(least_upper_bound(least_upper_bound(identity, identity), identity), X)) 119.57/119.83 = { by axiom 4 (symmetry_of_lub) } 119.57/119.83 least_upper_bound(Y, multiply(least_upper_bound(identity, least_upper_bound(identity, identity)), X)) 119.57/119.83 = { by lemma 23 } 119.57/119.83 least_upper_bound(Y, multiply(least_upper_bound(identity, least_upper_bound(identity, least_upper_bound(identity, inverse(least_upper_bound(?, identity))))), X)) 119.57/119.83 = { by axiom 11 (associativity_of_lub) } 119.57/119.83 least_upper_bound(Y, multiply(least_upper_bound(identity, least_upper_bound(least_upper_bound(identity, identity), inverse(least_upper_bound(?, identity)))), X)) 119.57/119.83 = { by axiom 11 (associativity_of_lub) } 119.57/119.83 least_upper_bound(Y, multiply(least_upper_bound(least_upper_bound(identity, least_upper_bound(identity, identity)), inverse(least_upper_bound(?, identity))), X)) 119.57/119.83 = { by axiom 4 (symmetry_of_lub) } 119.57/119.83 least_upper_bound(Y, multiply(least_upper_bound(inverse(least_upper_bound(?, identity)), least_upper_bound(identity, least_upper_bound(identity, identity))), X)) 119.57/119.83 = { by lemma 12 } 119.57/119.83 least_upper_bound(Y, multiply(least_upper_bound(identity, least_upper_bound(inverse(least_upper_bound(?, identity)), least_upper_bound(identity, identity))), X)) 119.57/119.83 = { by axiom 3 (left_identity) } 119.57/119.83 least_upper_bound(Y, multiply(least_upper_bound(identity, least_upper_bound(inverse(least_upper_bound(?, identity)), multiply(identity, least_upper_bound(identity, identity)))), X)) 119.57/119.83 = { by lemma 24 } 119.57/119.83 least_upper_bound(Y, multiply(least_upper_bound(identity, multiply(least_upper_bound(multiply(inverse(least_upper_bound(?, identity)), inverse(least_upper_bound(identity, identity))), identity), least_upper_bound(identity, identity))), X)) 119.57/119.83 = { by lemma 25 } 119.57/119.83 least_upper_bound(Y, multiply(least_upper_bound(identity, least_upper_bound(identity, least_upper_bound(identity, multiply(multiply(inverse(least_upper_bound(?, identity)), inverse(least_upper_bound(identity, identity))), least_upper_bound(identity, identity))))), X)) 119.57/119.83 = { by lemma 26 } 119.57/119.83 least_upper_bound(Y, multiply(least_upper_bound(identity, least_upper_bound(identity, multiply(multiply(inverse(least_upper_bound(?, identity)), inverse(least_upper_bound(identity, identity))), least_upper_bound(identity, identity)))), X)) 119.57/119.83 = { by lemma 25 } 119.57/119.83 least_upper_bound(Y, multiply(multiply(least_upper_bound(multiply(inverse(least_upper_bound(?, identity)), inverse(least_upper_bound(identity, identity))), identity), least_upper_bound(identity, identity)), X)) 119.57/119.83 = { by lemma 24 } 119.57/119.83 least_upper_bound(Y, multiply(least_upper_bound(inverse(least_upper_bound(?, identity)), multiply(identity, least_upper_bound(identity, identity))), X)) 119.57/119.83 = { by axiom 3 (left_identity) } 119.57/119.83 least_upper_bound(Y, multiply(least_upper_bound(inverse(least_upper_bound(?, identity)), least_upper_bound(identity, identity)), X)) 119.57/119.83 = { by lemma 12 } 119.57/119.83 least_upper_bound(Y, multiply(least_upper_bound(identity, least_upper_bound(inverse(least_upper_bound(?, identity)), identity)), X)) 119.57/119.83 = { by axiom 11 (associativity_of_lub) } 119.57/119.83 least_upper_bound(Y, multiply(least_upper_bound(least_upper_bound(identity, inverse(least_upper_bound(?, identity))), identity), X)) 119.57/119.83 = { by lemma 23 } 119.57/119.83 least_upper_bound(Y, multiply(least_upper_bound(identity, identity), X)) 119.57/119.83 = { by axiom 8 (idempotence_of_lub) } 119.57/119.83 least_upper_bound(Y, multiply(identity, X)) 119.57/119.83 = { by axiom 3 (left_identity) } 119.57/119.83 least_upper_bound(Y, X) 119.57/119.83 = { by axiom 4 (symmetry_of_lub) } 119.57/119.83 least_upper_bound(X, Y) 119.57/119.83 119.57/119.83 Lemma 27: multiply(Y, least_upper_bound(Z, multiply(inverse(Y), X))) = least_upper_bound(X, multiply(Y, Z)). 119.57/119.83 Proof: 119.57/119.83 multiply(Y, least_upper_bound(Z, multiply(inverse(Y), X))) 119.57/119.83 = { by lemma 14 } 119.57/119.83 multiply(inverse(inverse(Y)), least_upper_bound(Z, multiply(inverse(Y), X))) 119.57/119.83 = { by lemma 18 } 119.57/119.83 multiply(inverse(inverse(Y)), multiply(inverse(Y), least_upper_bound(X, multiply(Y, Z)))) 119.57/119.83 = { by lemma 13 } 119.57/119.83 least_upper_bound(X, multiply(Y, Z)) 119.57/119.83 119.57/119.83 Lemma 28: least_upper_bound(multiply(least_upper_bound(Y, identity), X), Z) = least_upper_bound(X, least_upper_bound(Z, multiply(Y, X))). 119.57/119.83 Proof: 119.57/119.83 least_upper_bound(multiply(least_upper_bound(Y, identity), X), Z) 119.57/119.83 = { by lemma 19 } 119.57/119.83 least_upper_bound(least_upper_bound(X, multiply(Y, X)), Z) 119.57/119.83 = { by axiom 11 (associativity_of_lub) } 119.57/119.83 least_upper_bound(X, least_upper_bound(multiply(Y, X), Z)) 119.57/119.83 = { by axiom 4 (symmetry_of_lub) } 119.57/119.85 least_upper_bound(X, least_upper_bound(Z, multiply(Y, X))) 119.57/119.85 119.57/119.85 Goal 1 (prove_p22a): multiply(least_upper_bound(a, identity), least_upper_bound(b, identity)) = least_upper_bound(least_upper_bound(multiply(a, b), identity), multiply(least_upper_bound(a, identity), least_upper_bound(b, identity))). 119.57/119.85 Proof: 119.57/119.85 multiply(least_upper_bound(a, identity), least_upper_bound(b, identity)) 119.57/119.85 = { by axiom 4 (symmetry_of_lub) } 119.57/119.85 multiply(least_upper_bound(identity, a), least_upper_bound(b, identity)) 119.57/119.85 = { by lemma 17 } 119.57/119.85 multiply(inverse(inverse(least_upper_bound(identity, a))), least_upper_bound(b, identity)) 119.57/119.85 = { by axiom 5 (glb_absorbtion) } 119.57/119.85 multiply(inverse(inverse(least_upper_bound(identity, a))), least_upper_bound(b, greatest_lower_bound(identity, least_upper_bound(identity, inverse(least_upper_bound(identity, a)))))) 119.57/119.85 = { by axiom 1 (left_inverse) } 119.57/119.85 multiply(inverse(inverse(least_upper_bound(identity, a))), least_upper_bound(b, greatest_lower_bound(multiply(inverse(least_upper_bound(identity, a)), least_upper_bound(identity, a)), least_upper_bound(identity, inverse(least_upper_bound(identity, a)))))) 119.57/119.85 = { by lemma 20 } 119.57/119.85 multiply(inverse(inverse(least_upper_bound(identity, a))), least_upper_bound(b, greatest_lower_bound(multiply(inverse(least_upper_bound(identity, a)), least_upper_bound(identity, a)), multiply(inverse(least_upper_bound(identity, a)), least_upper_bound(least_upper_bound(identity, a), identity))))) 119.57/119.85 = { by axiom 11 (associativity_of_lub) } 119.57/119.85 multiply(inverse(inverse(least_upper_bound(identity, a))), least_upper_bound(b, greatest_lower_bound(multiply(inverse(least_upper_bound(identity, a)), least_upper_bound(identity, a)), multiply(inverse(least_upper_bound(identity, a)), least_upper_bound(identity, least_upper_bound(a, identity)))))) 119.57/119.85 = { by axiom 6 (monotony_glb1) } 119.57/119.85 multiply(inverse(inverse(least_upper_bound(identity, a))), least_upper_bound(b, multiply(inverse(least_upper_bound(identity, a)), greatest_lower_bound(least_upper_bound(identity, a), least_upper_bound(identity, least_upper_bound(a, identity)))))) 119.57/119.85 = { by axiom 7 (symmetry_of_glb) } 119.57/119.85 multiply(inverse(inverse(least_upper_bound(identity, a))), least_upper_bound(b, multiply(inverse(least_upper_bound(identity, a)), greatest_lower_bound(least_upper_bound(identity, least_upper_bound(a, identity)), least_upper_bound(identity, a))))) 119.57/119.85 = { by lemma 18 } 119.57/119.85 least_upper_bound(greatest_lower_bound(least_upper_bound(identity, least_upper_bound(a, identity)), least_upper_bound(identity, a)), multiply(inverse(inverse(least_upper_bound(identity, a))), b)) 119.57/119.85 = { by lemma 17 } 119.57/119.85 least_upper_bound(greatest_lower_bound(least_upper_bound(identity, least_upper_bound(a, identity)), least_upper_bound(identity, a)), multiply(least_upper_bound(identity, a), b)) 119.57/119.85 = { by axiom 4 (symmetry_of_lub) } 119.57/119.85 least_upper_bound(multiply(least_upper_bound(identity, a), b), greatest_lower_bound(least_upper_bound(identity, least_upper_bound(a, identity)), least_upper_bound(identity, a))) 119.57/119.85 = { by axiom 7 (symmetry_of_glb) } 119.57/119.85 least_upper_bound(multiply(least_upper_bound(identity, a), b), greatest_lower_bound(least_upper_bound(identity, a), least_upper_bound(identity, least_upper_bound(a, identity)))) 119.57/119.85 = { by axiom 11 (associativity_of_lub) } 119.57/119.85 least_upper_bound(multiply(least_upper_bound(identity, a), b), greatest_lower_bound(least_upper_bound(identity, a), least_upper_bound(least_upper_bound(identity, a), identity))) 119.57/119.85 = { by axiom 5 (glb_absorbtion) } 119.57/119.85 least_upper_bound(multiply(least_upper_bound(identity, a), b), least_upper_bound(identity, a)) 119.57/119.85 = { by lemma 12 } 119.57/119.85 least_upper_bound(identity, least_upper_bound(multiply(least_upper_bound(identity, a), b), a)) 119.57/119.85 = { by axiom 4 (symmetry_of_lub) } 119.57/119.85 least_upper_bound(identity, least_upper_bound(a, multiply(least_upper_bound(identity, a), b))) 119.57/119.85 = { by axiom 8 (idempotence_of_lub) } 119.57/119.85 least_upper_bound(identity, least_upper_bound(a, multiply(least_upper_bound(identity, least_upper_bound(a, a)), b))) 119.57/119.85 = { by axiom 11 (associativity_of_lub) } 119.57/119.85 least_upper_bound(identity, least_upper_bound(a, multiply(least_upper_bound(least_upper_bound(identity, a), a), b))) 119.57/119.85 = { by lemma 26 } 119.57/119.85 least_upper_bound(identity, least_upper_bound(identity, least_upper_bound(a, multiply(least_upper_bound(least_upper_bound(identity, a), a), b)))) 119.57/119.85 = { by axiom 11 (associativity_of_lub) } 119.57/119.85 least_upper_bound(identity, least_upper_bound(least_upper_bound(identity, a), multiply(least_upper_bound(least_upper_bound(identity, a), a), b))) 119.57/119.85 = { by lemma 16 } 119.57/119.85 least_upper_bound(identity, least_upper_bound(least_upper_bound(identity, a), multiply(least_upper_bound(least_upper_bound(identity, a), multiply(a, identity)), b))) 119.57/119.85 = { by lemma 27 } 119.57/119.85 least_upper_bound(identity, least_upper_bound(least_upper_bound(identity, a), multiply(multiply(a, least_upper_bound(identity, multiply(inverse(a), least_upper_bound(identity, a)))), b))) 119.57/119.85 = { by axiom 2 (associativity) } 119.57/119.85 least_upper_bound(identity, least_upper_bound(least_upper_bound(identity, a), multiply(a, multiply(least_upper_bound(identity, multiply(inverse(a), least_upper_bound(identity, a))), b)))) 119.57/119.85 = { by lemma 27 } 119.57/119.85 least_upper_bound(identity, multiply(a, least_upper_bound(multiply(least_upper_bound(identity, multiply(inverse(a), least_upper_bound(identity, a))), b), multiply(inverse(a), least_upper_bound(identity, a))))) 119.57/119.85 = { by axiom 4 (symmetry_of_lub) } 119.57/119.85 least_upper_bound(identity, multiply(a, least_upper_bound(multiply(least_upper_bound(multiply(inverse(a), least_upper_bound(identity, a)), identity), b), multiply(inverse(a), least_upper_bound(identity, a))))) 119.57/119.85 = { by lemma 28 } 119.57/119.85 least_upper_bound(identity, multiply(a, least_upper_bound(b, least_upper_bound(multiply(inverse(a), least_upper_bound(identity, a)), multiply(multiply(inverse(a), least_upper_bound(identity, a)), b))))) 119.57/119.85 = { by lemma 16 } 119.57/119.85 least_upper_bound(identity, multiply(a, least_upper_bound(b, least_upper_bound(multiply(multiply(inverse(a), least_upper_bound(identity, a)), identity), multiply(multiply(inverse(a), least_upper_bound(identity, a)), b))))) 119.57/119.85 = { by axiom 10 (monotony_lub1) } 119.57/119.85 least_upper_bound(identity, multiply(a, least_upper_bound(b, multiply(multiply(inverse(a), least_upper_bound(identity, a)), least_upper_bound(identity, b))))) 119.57/119.85 = { by axiom 4 (symmetry_of_lub) } 119.57/119.85 least_upper_bound(identity, multiply(a, least_upper_bound(b, multiply(multiply(inverse(a), least_upper_bound(identity, a)), least_upper_bound(b, identity))))) 119.57/119.85 = { by axiom 2 (associativity) } 119.57/119.85 least_upper_bound(identity, multiply(a, least_upper_bound(b, multiply(inverse(a), multiply(least_upper_bound(identity, a), least_upper_bound(b, identity)))))) 119.57/119.85 = { by lemma 27 } 119.57/119.85 least_upper_bound(identity, least_upper_bound(multiply(least_upper_bound(identity, a), least_upper_bound(b, identity)), multiply(a, b))) 119.57/119.85 = { by axiom 4 (symmetry_of_lub) } 119.57/119.85 least_upper_bound(identity, least_upper_bound(multiply(least_upper_bound(a, identity), least_upper_bound(b, identity)), multiply(a, b))) 119.57/119.85 = { by lemma 19 } 119.57/119.85 least_upper_bound(identity, least_upper_bound(least_upper_bound(least_upper_bound(b, identity), multiply(a, least_upper_bound(b, identity))), multiply(a, b))) 119.57/119.85 = { by axiom 11 (associativity_of_lub) } 119.57/119.85 least_upper_bound(identity, least_upper_bound(least_upper_bound(b, identity), least_upper_bound(multiply(a, least_upper_bound(b, identity)), multiply(a, b)))) 119.57/119.85 = { by lemma 12 } 119.57/119.85 least_upper_bound(least_upper_bound(b, identity), least_upper_bound(identity, least_upper_bound(multiply(a, least_upper_bound(b, identity)), multiply(a, b)))) 119.57/119.85 = { by lemma 12 } 119.57/119.85 least_upper_bound(least_upper_bound(b, identity), least_upper_bound(multiply(a, least_upper_bound(b, identity)), least_upper_bound(identity, multiply(a, b)))) 119.57/119.85 = { by lemma 22 } 119.57/119.85 least_upper_bound(least_upper_bound(identity, multiply(a, b)), multiply(least_upper_bound(a, identity), least_upper_bound(b, identity))) 119.57/119.85 = { by axiom 4 (symmetry_of_lub) } 119.57/119.85 least_upper_bound(least_upper_bound(identity, multiply(a, b)), multiply(least_upper_bound(identity, a), least_upper_bound(b, identity))) 119.57/119.85 = { by axiom 11 (associativity_of_lub) } 119.57/119.85 least_upper_bound(identity, least_upper_bound(multiply(a, b), multiply(least_upper_bound(identity, a), least_upper_bound(b, identity)))) 119.57/119.85 = { by lemma 12 } 119.57/119.85 least_upper_bound(multiply(a, b), least_upper_bound(identity, multiply(least_upper_bound(identity, a), least_upper_bound(b, identity)))) 119.57/119.85 = { by axiom 4 (symmetry_of_lub) } 119.57/119.85 least_upper_bound(multiply(a, b), least_upper_bound(identity, multiply(least_upper_bound(a, identity), least_upper_bound(b, identity)))) 119.57/119.85 = { by axiom 11 (associativity_of_lub) } 119.57/119.85 least_upper_bound(least_upper_bound(multiply(a, b), identity), multiply(least_upper_bound(a, identity), least_upper_bound(b, identity))) 119.57/119.85 % SZS output end Proof 119.57/119.85 119.57/119.85 RESULT: Unsatisfiable (the axioms are contradictory). 119.57/119.86 EOF