0.07/0.13 % Problem : theBenchmark.p : TPTP v0.0.0. Released v0.0.0. 0.07/0.13 % Command : twee %s --tstp --casc --quiet --explain-encoding --conditional-encoding if --smaller --drop-non-horn 0.13/0.35 % Computer : n020.cluster.edu 0.13/0.35 % Model : x86_64 x86_64 0.13/0.35 % CPU : Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz 0.13/0.35 % Memory : 8042.1875MB 0.13/0.35 % OS : Linux 3.10.0-693.el7.x86_64 0.13/0.35 % CPULimit : 180 0.13/0.35 % DateTime : Thu Aug 29 13:32:25 EDT 2019 0.13/0.35 % CPUTime : 31.84/32.01 % SZS status Unsatisfiable 31.84/32.01 31.84/32.02 % SZS output start Proof 31.84/32.02 Take the following subset of the input axioms: 31.89/32.05 fof(absorption1, axiom, ![X, Y]: X=meet(X, join(X, Y))). 31.89/32.05 fof(absorption2, axiom, ![X, Y]: join(X, meet(X, Y))=X). 31.89/32.05 fof(associativity_of_join, axiom, ![X, Y, Z]: join(join(X, Y), Z)=join(X, join(Y, Z))). 31.89/32.05 fof(associativity_of_meet, axiom, ![X, Y, Z]: meet(X, meet(Y, Z))=meet(meet(X, Y), Z)). 31.89/32.05 fof(commutativity_of_join, axiom, ![X, Y]: join(Y, X)=join(X, Y)). 31.89/32.05 fof(commutativity_of_meet, axiom, ![X, Y]: meet(Y, X)=meet(X, Y)). 31.89/32.05 fof(complement_join, axiom, ![X]: one=join(X, complement(X))). 31.89/32.05 fof(complement_meet, axiom, ![X]: meet(X, complement(X))=zero). 31.89/32.05 fof(equation_H6, axiom, ![X, Y, Z]: meet(X, join(Y, meet(X, Z)))=meet(X, join(meet(X, join(Y, meet(X, Z))), meet(Z, join(X, Y))))). 31.89/32.05 fof(idempotence_of_join, axiom, ![X]: X=join(X, X)). 31.89/32.05 fof(ifeq_axiom, axiom, ![A, B, C]: ifeq(A, A, B, C)=B). 31.89/32.05 fof(meet_join_complement, axiom, ![X, Y]: Y=ifeq(join(X, Y), one, ifeq(meet(X, Y), zero, complement(X), Y), Y)). 31.89/32.05 fof(prove_distributivity, negated_conjecture, complement(a)!=join(complement(b), complement(a))). 31.89/32.05 fof(prove_distributivity_hypothesis, hypothesis, a=meet(b, a)). 31.89/32.05 31.89/32.05 Now clausify the problem and encode Horn clauses using encoding 3 of 31.89/32.05 http://www.cse.chalmers.se/~nicsma/papers/horn.pdf. 31.89/32.05 We repeatedly replace C & s=t => u=v by the two clauses: 31.89/32.05 fresh(y, y, x1...xn) = u 31.89/32.05 C => fresh(s, t, x1...xn) = v 31.89/32.05 where fresh is a fresh function symbol and x1..xn are the free 31.89/32.05 variables of u and v. 31.89/32.05 A predicate p(X) is encoded as p(X)=true (this is sound, because the 31.89/32.05 input problem has no model of domain size 1). 31.89/32.05 31.89/32.05 The encoding turns the above axioms into the following unit equations and goals: 31.89/32.05 31.89/32.05 Axiom 1 (complement_join): one = join(X, complement(X)). 31.89/32.05 Axiom 2 (absorption2): join(X, meet(X, Y)) = X. 31.89/32.05 Axiom 3 (complement_meet): meet(X, complement(X)) = zero. 31.89/32.05 Axiom 4 (associativity_of_meet): meet(X, meet(Y, Z)) = meet(meet(X, Y), Z). 31.89/32.05 Axiom 5 (equation_H6): meet(X, join(Y, meet(X, Z))) = meet(X, join(meet(X, join(Y, meet(X, Z))), meet(Z, join(X, Y)))). 31.89/32.05 Axiom 6 (meet_join_complement): X = ifeq(join(Y, X), one, ifeq(meet(Y, X), zero, complement(Y), X), X). 31.89/32.05 Axiom 7 (ifeq_axiom): ifeq(X, X, Y, Z) = Y. 31.89/32.05 Axiom 8 (absorption1): X = meet(X, join(X, Y)). 31.89/32.05 Axiom 9 (commutativity_of_meet): meet(X, Y) = meet(Y, X). 31.89/32.05 Axiom 10 (commutativity_of_join): join(X, Y) = join(Y, X). 31.89/32.05 Axiom 11 (prove_distributivity_hypothesis): a = meet(b, a). 31.89/32.05 Axiom 12 (idempotence_of_join): X = join(X, X). 31.99/32.21 Axiom 13 (associativity_of_join): join(join(X, Y), Z) = join(X, join(Y, Z)). 31.99/32.21 31.99/32.21 Lemma 14: ifeq(join(Y, X), one, ifeq(meet(X, Y), zero, complement(Y), X), X) = X. 31.99/32.21 Proof: 31.99/32.21 ifeq(join(Y, X), one, ifeq(meet(X, Y), zero, complement(Y), X), X) 31.99/32.21 = { by axiom 9 (commutativity_of_meet) } 31.99/32.21 ifeq(join(Y, X), one, ifeq(meet(Y, X), zero, complement(Y), X), X) 31.99/32.21 = { by axiom 6 (meet_join_complement) } 31.99/32.21 X 31.99/32.21 31.99/32.21 Lemma 15: complement(complement(X)) = X. 31.99/32.21 Proof: 31.99/32.21 complement(complement(X)) 31.99/32.21 = { by axiom 7 (ifeq_axiom) } 31.99/32.21 ifeq(one, one, complement(complement(X)), X) 31.99/32.21 = { by axiom 1 (complement_join) } 31.99/32.21 ifeq(join(X, complement(X)), one, complement(complement(X)), X) 31.99/32.21 = { by axiom 10 (commutativity_of_join) } 31.99/32.21 ifeq(join(complement(X), X), one, complement(complement(X)), X) 31.99/32.21 = { by axiom 7 (ifeq_axiom) } 31.99/32.21 ifeq(join(complement(X), X), one, ifeq(zero, zero, complement(complement(X)), X), X) 31.99/32.21 = { by axiom 3 (complement_meet) } 31.99/32.21 ifeq(join(complement(X), X), one, ifeq(meet(X, complement(X)), zero, complement(complement(X)), X), X) 31.99/32.21 = { by lemma 14 } 31.99/32.21 X 31.99/32.21 31.99/32.21 Lemma 16: meet(a, b) = a. 31.99/32.21 Proof: 31.99/32.21 meet(a, b) 31.99/32.21 = { by axiom 9 (commutativity_of_meet) } 31.99/32.21 meet(b, a) 31.99/32.21 = { by axiom 11 (prove_distributivity_hypothesis) } 31.99/32.21 a 31.99/32.21 31.99/32.21 Lemma 17: join(X, meet(Y, X)) = X. 31.99/32.21 Proof: 31.99/32.21 join(X, meet(Y, X)) 31.99/32.21 = { by axiom 9 (commutativity_of_meet) } 31.99/32.21 join(X, meet(X, Y)) 31.99/32.21 = { by axiom 2 (absorption2) } 31.99/32.21 X 31.99/32.21 31.99/32.21 Lemma 18: meet(X, join(Y, X)) = X. 31.99/32.21 Proof: 31.99/32.21 meet(X, join(Y, X)) 31.99/32.21 = { by axiom 10 (commutativity_of_join) } 31.99/32.21 meet(X, join(X, Y)) 31.99/32.21 = { by axiom 8 (absorption1) } 31.99/32.21 X 31.99/32.21 31.99/32.21 Lemma 19: meet(join(X, Y), join(X, meet(Y, Z))) = join(X, meet(Y, Z)). 31.99/32.21 Proof: 31.99/32.21 meet(join(X, Y), join(X, meet(Y, Z))) 31.99/32.21 = { by axiom 10 (commutativity_of_join) } 31.99/32.21 meet(join(Y, X), join(X, meet(Y, Z))) 31.99/32.21 = { by axiom 9 (commutativity_of_meet) } 31.99/32.21 meet(join(X, meet(Y, Z)), join(Y, X)) 31.99/32.21 = { by axiom 2 (absorption2) } 31.99/32.21 meet(join(X, meet(Y, Z)), join(join(Y, meet(Y, Z)), X)) 31.99/32.21 = { by axiom 13 (associativity_of_join) } 31.99/32.21 meet(join(X, meet(Y, Z)), join(Y, join(meet(Y, Z), X))) 31.99/32.21 = { by axiom 10 (commutativity_of_join) } 31.99/32.21 meet(join(X, meet(Y, Z)), join(Y, join(X, meet(Y, Z)))) 31.99/32.21 = { by lemma 18 } 31.99/32.21 join(X, meet(Y, Z)) 31.99/32.21 31.99/32.21 Lemma 20: join(X, join(Y, Z)) = join(Z, join(X, Y)). 31.99/32.21 Proof: 31.99/32.21 join(X, join(Y, Z)) 31.99/32.21 = { by axiom 13 (associativity_of_join) } 31.99/32.21 join(join(X, Y), Z) 31.99/32.21 = { by axiom 10 (commutativity_of_join) } 31.99/32.21 join(Z, join(X, Y)) 31.99/32.21 31.99/32.21 Lemma 21: meet(X, one) = X. 31.99/32.21 Proof: 31.99/32.21 meet(X, one) 31.99/32.21 = { by axiom 1 (complement_join) } 31.99/32.21 meet(X, join(X, complement(X))) 31.99/32.21 = { by axiom 8 (absorption1) } 31.99/32.21 X 31.99/32.21 31.99/32.21 Lemma 22: join(X, one) = one. 31.99/32.21 Proof: 31.99/32.21 join(X, one) 31.99/32.21 = { by axiom 10 (commutativity_of_join) } 31.99/32.21 join(one, X) 31.99/32.21 = { by lemma 21 } 31.99/32.21 join(one, meet(X, one)) 31.99/32.21 = { by axiom 9 (commutativity_of_meet) } 31.99/32.21 join(one, meet(one, X)) 31.99/32.21 = { by axiom 2 (absorption2) } 31.99/32.21 one 31.99/32.21 31.99/32.21 Lemma 23: join(X, zero) = X. 31.99/32.21 Proof: 31.99/32.21 join(X, zero) 31.99/32.21 = { by axiom 3 (complement_meet) } 31.99/32.21 join(X, meet(X, complement(X))) 31.99/32.21 = { by axiom 2 (absorption2) } 31.99/32.21 X 31.99/32.21 31.99/32.21 Lemma 24: join(zero, X) = X. 31.99/32.21 Proof: 31.99/32.21 join(zero, X) 31.99/32.21 = { by axiom 10 (commutativity_of_join) } 31.99/32.21 join(X, zero) 31.99/32.21 = { by lemma 23 } 31.99/32.21 X 31.99/32.21 31.99/32.21 Lemma 25: complement(zero) = one. 31.99/32.21 Proof: 31.99/32.21 complement(zero) 31.99/32.21 = { by lemma 24 } 31.99/32.21 join(zero, complement(zero)) 31.99/32.21 = { by axiom 1 (complement_join) } 31.99/32.21 one 31.99/32.21 31.99/32.21 Lemma 26: meet(a, meet(b, X)) = meet(X, a). 31.99/32.21 Proof: 31.99/32.21 meet(a, meet(b, X)) 31.99/32.21 = { by axiom 9 (commutativity_of_meet) } 31.99/32.21 meet(a, meet(X, b)) 31.99/32.21 = { by axiom 9 (commutativity_of_meet) } 31.99/32.21 meet(a, meet(b, X)) 31.99/32.21 = { by axiom 4 (associativity_of_meet) } 31.99/32.21 meet(meet(a, b), X) 31.99/32.21 = { by lemma 16 } 31.99/32.21 meet(a, X) 31.99/32.21 = { by axiom 9 (commutativity_of_meet) } 31.99/32.21 meet(X, a) 31.99/32.21 31.99/32.21 Lemma 27: join(b, meet(X, a)) = b. 31.99/32.21 Proof: 31.99/32.21 join(b, meet(X, a)) 31.99/32.21 = { by lemma 26 } 31.99/32.21 join(b, meet(a, meet(b, X))) 31.99/32.21 = { by axiom 9 (commutativity_of_meet) } 31.99/32.21 join(b, meet(a, meet(X, b))) 31.99/32.21 = { by axiom 4 (associativity_of_meet) } 31.99/32.21 join(b, meet(meet(a, X), b)) 31.99/32.21 = { by lemma 17 } 31.99/32.21 b 31.99/32.21 31.99/32.21 Lemma 28: meet(X, meet(join(X, Z), Y)) = meet(X, Y). 31.99/32.21 Proof: 31.99/32.21 meet(X, meet(join(X, Z), Y)) 31.99/32.21 = { by axiom 9 (commutativity_of_meet) } 31.99/32.21 meet(X, meet(Y, join(X, Z))) 31.99/32.21 = { by axiom 9 (commutativity_of_meet) } 31.99/32.21 meet(X, meet(join(X, Z), Y)) 31.99/32.21 = { by axiom 4 (associativity_of_meet) } 31.99/32.21 meet(meet(X, join(X, Z)), Y) 31.99/32.21 = { by axiom 8 (absorption1) } 31.99/32.21 meet(X, Y) 31.99/32.21 31.99/32.21 Lemma 29: meet(X, meet(Y, join(Z, X))) = meet(X, Y). 31.99/32.21 Proof: 31.99/32.21 meet(X, meet(Y, join(Z, X))) 31.99/32.21 = { by axiom 9 (commutativity_of_meet) } 31.99/32.21 meet(X, meet(join(Z, X), Y)) 31.99/32.21 = { by axiom 4 (associativity_of_meet) } 31.99/32.21 meet(meet(X, join(Z, X)), Y) 31.99/32.21 = { by axiom 9 (commutativity_of_meet) } 31.99/32.21 meet(Y, meet(X, join(Z, X))) 31.99/32.21 = { by lemma 18 } 31.99/32.21 meet(Y, X) 31.99/32.21 = { by axiom 9 (commutativity_of_meet) } 32.20/32.38 meet(X, Y) 32.20/32.38 32.20/32.38 Lemma 30: join(meet(b, complement(a)), complement(join(a, meet(b, complement(a))))) = complement(a). 32.20/32.38 Proof: 32.20/32.38 join(meet(b, complement(a)), complement(join(a, meet(b, complement(a))))) 32.20/32.38 = { by axiom 6 (meet_join_complement) } 32.20/32.38 ifeq(join(a, join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), one, ifeq(meet(a, join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 13 (associativity_of_join) } 32.20/32.38 ifeq(join(join(a, meet(b, complement(a))), complement(join(a, meet(b, complement(a))))), one, ifeq(meet(a, join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 1 (complement_join) } 32.20/32.38 ifeq(one, one, ifeq(meet(a, join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by lemma 15 } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 9 (commutativity_of_meet) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), join(meet(complement(a), b), complement(join(a, meet(b, complement(a)))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 9 (commutativity_of_meet) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), join(meet(complement(a), b), complement(join(a, meet(complement(a), b))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 10 (commutativity_of_join) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), join(complement(join(a, meet(complement(a), b))), meet(complement(a), b))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 10 (commutativity_of_join) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), join(complement(join(meet(complement(a), b), a)), meet(complement(a), b))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by lemma 15 } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), join(complement(join(meet(complement(a), b), complement(complement(a)))), meet(complement(a), b))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by lemma 27 } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), join(complement(join(meet(complement(a), b), complement(complement(a)))), meet(complement(a), join(b, meet(complement(a), a))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 5 (equation_H6) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), join(complement(join(meet(complement(a), b), complement(complement(a)))), meet(complement(a), join(meet(complement(a), join(b, meet(complement(a), a))), meet(a, join(complement(a), b)))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by lemma 27 } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), join(complement(join(meet(complement(a), b), complement(complement(a)))), meet(complement(a), join(meet(complement(a), b), meet(a, join(complement(a), b)))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 10 (commutativity_of_join) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), join(complement(join(meet(complement(a), b), complement(complement(a)))), meet(complement(a), join(meet(complement(a), b), meet(a, join(b, complement(a))))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 9 (commutativity_of_meet) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), join(complement(join(meet(complement(a), b), complement(complement(a)))), meet(complement(a), join(meet(complement(a), b), meet(join(b, complement(a)), a))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by lemma 26 } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), join(complement(join(meet(complement(a), b), complement(complement(a)))), meet(complement(a), join(meet(complement(a), b), meet(a, meet(b, join(b, complement(a)))))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 8 (absorption1) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), join(complement(join(meet(complement(a), b), complement(complement(a)))), meet(complement(a), join(meet(complement(a), b), meet(a, b))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by lemma 16 } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), join(complement(join(meet(complement(a), b), complement(complement(a)))), meet(complement(a), join(meet(complement(a), b), a)))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by lemma 15 } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), join(complement(join(meet(complement(a), b), complement(complement(a)))), meet(complement(a), join(meet(complement(a), b), complement(complement(a)))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by lemma 29 } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), meet(join(complement(join(meet(complement(a), b), complement(complement(a)))), meet(complement(a), join(meet(complement(a), b), complement(complement(a))))), join(meet(complement(a), b), complement(complement(a))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 9 (commutativity_of_meet) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), meet(join(meet(complement(a), b), complement(complement(a))), join(complement(join(meet(complement(a), b), complement(complement(a)))), meet(complement(a), join(meet(complement(a), b), complement(complement(a))))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 9 (commutativity_of_meet) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), meet(join(meet(complement(a), b), complement(complement(a))), join(complement(join(meet(complement(a), b), complement(complement(a)))), meet(join(meet(complement(a), b), complement(complement(a))), complement(a))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 10 (commutativity_of_join) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), meet(join(meet(complement(a), b), complement(complement(a))), join(meet(join(meet(complement(a), b), complement(complement(a))), complement(a)), complement(join(meet(complement(a), b), complement(complement(a))))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by lemma 21 } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), meet(join(meet(complement(a), b), complement(complement(a))), join(meet(join(meet(complement(a), b), complement(complement(a))), complement(a)), meet(complement(join(meet(complement(a), b), complement(complement(a)))), one)))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by lemma 22 } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), meet(join(meet(complement(a), b), complement(complement(a))), join(meet(join(meet(complement(a), b), complement(complement(a))), complement(a)), meet(complement(join(meet(complement(a), b), complement(complement(a)))), join(meet(complement(a), b), one))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 10 (commutativity_of_join) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), meet(join(meet(complement(a), b), complement(complement(a))), join(meet(join(meet(complement(a), b), complement(complement(a))), complement(a)), meet(complement(join(meet(complement(a), b), complement(complement(a)))), join(one, meet(complement(a), b)))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 1 (complement_join) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), meet(join(meet(complement(a), b), complement(complement(a))), join(meet(join(meet(complement(a), b), complement(complement(a))), complement(a)), meet(complement(join(meet(complement(a), b), complement(complement(a)))), join(join(complement(a), complement(complement(a))), meet(complement(a), b)))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 13 (associativity_of_join) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), meet(join(meet(complement(a), b), complement(complement(a))), join(meet(join(meet(complement(a), b), complement(complement(a))), complement(a)), meet(complement(join(meet(complement(a), b), complement(complement(a)))), join(complement(a), join(complement(complement(a)), meet(complement(a), b))))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 10 (commutativity_of_join) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), meet(join(meet(complement(a), b), complement(complement(a))), join(meet(join(meet(complement(a), b), complement(complement(a))), complement(a)), meet(complement(join(meet(complement(a), b), complement(complement(a)))), join(complement(a), join(meet(complement(a), b), complement(complement(a)))))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 10 (commutativity_of_join) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), meet(join(meet(complement(a), b), complement(complement(a))), join(meet(join(meet(complement(a), b), complement(complement(a))), complement(a)), meet(complement(join(meet(complement(a), b), complement(complement(a)))), join(join(meet(complement(a), b), complement(complement(a))), complement(a)))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 10 (commutativity_of_join) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), meet(join(meet(complement(a), b), complement(complement(a))), join(meet(complement(join(meet(complement(a), b), complement(complement(a)))), join(join(meet(complement(a), b), complement(complement(a))), complement(a))), meet(join(meet(complement(a), b), complement(complement(a))), complement(a))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by lemma 23 } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), meet(join(meet(complement(a), b), complement(complement(a))), join(meet(complement(join(meet(complement(a), b), complement(complement(a)))), join(join(meet(complement(a), b), complement(complement(a))), complement(a))), meet(join(meet(complement(a), b), complement(complement(a))), join(complement(a), zero))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 3 (complement_meet) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), meet(join(meet(complement(a), b), complement(complement(a))), join(meet(complement(join(meet(complement(a), b), complement(complement(a)))), join(join(meet(complement(a), b), complement(complement(a))), complement(a))), meet(join(meet(complement(a), b), complement(complement(a))), join(complement(a), meet(join(meet(complement(a), b), complement(complement(a))), complement(join(meet(complement(a), b), complement(complement(a)))))))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 10 (commutativity_of_join) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), meet(join(meet(complement(a), b), complement(complement(a))), join(meet(join(meet(complement(a), b), complement(complement(a))), join(complement(a), meet(join(meet(complement(a), b), complement(complement(a))), complement(join(meet(complement(a), b), complement(complement(a))))))), meet(complement(join(meet(complement(a), b), complement(complement(a)))), join(join(meet(complement(a), b), complement(complement(a))), complement(a)))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 5 (equation_H6) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), meet(join(meet(complement(a), b), complement(complement(a))), join(complement(a), meet(join(meet(complement(a), b), complement(complement(a))), complement(join(meet(complement(a), b), complement(complement(a)))))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 3 (complement_meet) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), meet(join(meet(complement(a), b), complement(complement(a))), join(complement(a), zero))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by lemma 23 } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), meet(join(meet(complement(a), b), complement(complement(a))), complement(a))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 9 (commutativity_of_meet) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), meet(complement(a), join(meet(complement(a), b), complement(complement(a))))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by lemma 29 } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(complement(a)), complement(a)), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 9 (commutativity_of_meet) } 32.20/32.38 ifeq(one, one, ifeq(meet(complement(a), complement(complement(a))), zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 3 (complement_meet) } 32.20/32.38 ifeq(one, one, ifeq(zero, zero, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 7 (ifeq_axiom) } 32.20/32.38 ifeq(one, one, complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.20/32.38 = { by axiom 7 (ifeq_axiom) } 32.20/32.39 complement(a) 32.20/32.39 32.20/32.39 Lemma 31: meet(b, complement(join(a, meet(b, complement(a))))) = zero. 32.20/32.39 Proof: 32.20/32.39 meet(b, complement(join(a, meet(b, complement(a))))) 32.20/32.39 = { by axiom 9 (commutativity_of_meet) } 32.20/32.39 meet(complement(join(a, meet(b, complement(a)))), b) 32.20/32.39 = { by lemma 28 } 32.20/32.39 meet(complement(join(a, meet(b, complement(a)))), meet(join(complement(join(a, meet(b, complement(a)))), meet(b, complement(a))), b)) 32.20/32.39 = { by axiom 8 (absorption1) } 32.20/32.39 meet(complement(join(a, meet(b, complement(a)))), meet(meet(join(complement(join(a, meet(b, complement(a)))), meet(b, complement(a))), b), join(meet(join(complement(join(a, meet(b, complement(a)))), meet(b, complement(a))), b), meet(?, a)))) 32.20/32.39 = { by axiom 4 (associativity_of_meet) } 32.20/32.39 meet(complement(join(a, meet(b, complement(a)))), meet(join(complement(join(a, meet(b, complement(a)))), meet(b, complement(a))), meet(b, join(meet(join(complement(join(a, meet(b, complement(a)))), meet(b, complement(a))), b), meet(?, a))))) 32.20/32.39 = { by axiom 10 (commutativity_of_join) } 32.20/32.39 meet(complement(join(a, meet(b, complement(a)))), meet(join(complement(join(a, meet(b, complement(a)))), meet(b, complement(a))), meet(b, join(meet(?, a), meet(join(complement(join(a, meet(b, complement(a)))), meet(b, complement(a))), b))))) 32.20/32.39 = { by lemma 28 } 32.20/32.39 meet(complement(join(a, meet(b, complement(a)))), meet(b, join(meet(?, a), meet(join(complement(join(a, meet(b, complement(a)))), meet(b, complement(a))), b)))) 32.20/32.39 = { by lemma 27 } 32.20/32.39 meet(complement(join(a, meet(b, complement(a)))), meet(join(b, meet(?, a)), join(meet(?, a), meet(join(complement(join(a, meet(b, complement(a)))), meet(b, complement(a))), b)))) 32.20/32.39 = { by axiom 10 (commutativity_of_join) } 32.20/32.39 meet(complement(join(a, meet(b, complement(a)))), meet(join(meet(?, a), b), join(meet(?, a), meet(join(complement(join(a, meet(b, complement(a)))), meet(b, complement(a))), b)))) 32.20/32.39 = { by axiom 9 (commutativity_of_meet) } 32.20/32.39 meet(complement(join(a, meet(b, complement(a)))), meet(join(meet(?, a), b), join(meet(?, a), meet(b, join(complement(join(a, meet(b, complement(a)))), meet(b, complement(a))))))) 32.20/32.39 = { by lemma 19 } 32.20/32.39 meet(complement(join(a, meet(b, complement(a)))), join(meet(?, a), meet(b, join(complement(join(a, meet(b, complement(a)))), meet(b, complement(a)))))) 32.20/32.39 = { by axiom 10 (commutativity_of_join) } 32.20/32.39 meet(complement(join(a, meet(b, complement(a)))), join(meet(?, a), meet(b, join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))))) 32.20/32.39 = { by lemma 30 } 32.20/32.39 meet(complement(join(a, meet(b, complement(a)))), join(meet(?, a), meet(b, complement(a)))) 32.20/32.39 = { by axiom 10 (commutativity_of_join) } 32.20/32.39 meet(complement(join(a, meet(b, complement(a)))), join(meet(b, complement(a)), meet(?, a))) 32.20/32.39 = { by axiom 9 (commutativity_of_meet) } 32.20/32.39 meet(join(meet(b, complement(a)), meet(?, a)), complement(join(a, meet(b, complement(a))))) 32.20/32.39 = { by axiom 10 (commutativity_of_join) } 32.20/32.39 meet(join(meet(b, complement(a)), meet(?, a)), complement(join(meet(b, complement(a)), a))) 32.20/32.39 = { by lemma 17 } 32.20/32.39 meet(join(meet(b, complement(a)), meet(?, a)), complement(join(meet(b, complement(a)), join(a, meet(?, a))))) 32.20/32.39 = { by axiom 13 (associativity_of_join) } 32.20/32.39 meet(join(meet(b, complement(a)), meet(?, a)), complement(join(join(meet(b, complement(a)), a), meet(?, a)))) 32.20/32.39 = { by axiom 10 (commutativity_of_join) } 32.20/32.39 meet(join(meet(b, complement(a)), meet(?, a)), complement(join(join(a, meet(b, complement(a))), meet(?, a)))) 32.20/32.39 = { by axiom 13 (associativity_of_join) } 32.20/32.39 meet(join(meet(b, complement(a)), meet(?, a)), complement(join(a, join(meet(b, complement(a)), meet(?, a))))) 32.20/32.39 = { by axiom 10 (commutativity_of_join) } 32.20/32.39 meet(join(meet(b, complement(a)), meet(?, a)), complement(join(join(meet(b, complement(a)), meet(?, a)), a))) 32.20/32.39 = { by lemma 28 } 32.20/32.39 meet(join(meet(b, complement(a)), meet(?, a)), meet(join(join(meet(b, complement(a)), meet(?, a)), a), complement(join(join(meet(b, complement(a)), meet(?, a)), a)))) 32.20/32.39 = { by axiom 3 (complement_meet) } 32.20/32.39 meet(join(meet(b, complement(a)), meet(?, a)), zero) 32.20/32.39 = { by axiom 9 (commutativity_of_meet) } 32.20/32.39 meet(zero, join(meet(b, complement(a)), meet(?, a))) 32.20/32.39 = { by lemma 24 } 32.20/32.39 join(zero, meet(zero, join(meet(b, complement(a)), meet(?, a)))) 32.20/32.39 = { by axiom 2 (absorption2) } 32.26/32.42 zero 32.26/32.42 32.26/32.42 Goal 1 (prove_distributivity): complement(a) = join(complement(b), complement(a)). 32.26/32.42 Proof: 32.26/32.42 complement(a) 32.26/32.42 = { by axiom 12 (idempotence_of_join) } 32.26/32.42 join(complement(a), complement(a)) 32.26/32.42 = { by lemma 30 } 32.26/32.42 join(complement(a), join(meet(b, complement(a)), complement(join(a, meet(b, complement(a)))))) 32.26/32.42 = { by lemma 20 } 32.26/32.42 join(meet(b, complement(a)), join(complement(join(a, meet(b, complement(a)))), complement(a))) 32.26/32.42 = { by lemma 20 } 32.26/32.42 join(complement(join(a, meet(b, complement(a)))), join(complement(a), meet(b, complement(a)))) 32.26/32.42 = { by lemma 17 } 32.26/32.42 join(complement(join(a, meet(b, complement(a)))), complement(a)) 32.26/32.42 = { by axiom 10 (commutativity_of_join) } 32.26/32.42 join(complement(a), complement(join(a, meet(b, complement(a))))) 32.26/32.42 = { by lemma 15 } 32.26/32.42 join(complement(a), complement(complement(complement(join(a, meet(b, complement(a))))))) 32.26/32.42 = { by axiom 7 (ifeq_axiom) } 32.26/32.42 join(complement(a), complement(ifeq(one, one, complement(complement(join(a, meet(b, complement(a))))), b))) 32.26/32.42 = { by lemma 22 } 32.26/32.42 join(complement(a), complement(ifeq(join(b, one), one, complement(complement(join(a, meet(b, complement(a))))), b))) 32.26/32.42 = { by axiom 1 (complement_join) } 32.26/32.42 join(complement(a), complement(ifeq(join(b, join(meet(b, join(a, meet(complement(a), b))), complement(meet(b, join(a, meet(complement(a), b)))))), one, complement(complement(join(a, meet(b, complement(a))))), b))) 32.26/32.42 = { by lemma 20 } 32.26/32.42 join(complement(a), complement(ifeq(join(meet(b, join(a, meet(complement(a), b))), join(complement(meet(b, join(a, meet(complement(a), b)))), b)), one, complement(complement(join(a, meet(b, complement(a))))), b))) 32.26/32.42 = { by lemma 20 } 32.26/32.42 join(complement(a), complement(ifeq(join(complement(meet(b, join(a, meet(complement(a), b)))), join(b, meet(b, join(a, meet(complement(a), b))))), one, complement(complement(join(a, meet(b, complement(a))))), b))) 32.26/32.42 = { by axiom 2 (absorption2) } 32.26/32.42 join(complement(a), complement(ifeq(join(complement(meet(b, join(a, meet(complement(a), b)))), b), one, complement(complement(join(a, meet(b, complement(a))))), b))) 32.26/32.42 = { by axiom 10 (commutativity_of_join) } 32.26/32.42 join(complement(a), complement(ifeq(join(b, complement(meet(b, join(a, meet(complement(a), b))))), one, complement(complement(join(a, meet(b, complement(a))))), b))) 32.26/32.42 = { by lemma 17 } 32.26/32.42 join(complement(a), complement(ifeq(join(b, complement(meet(join(b, meet(a, b)), join(a, meet(complement(a), b))))), one, complement(complement(join(a, meet(b, complement(a))))), b))) 32.26/32.42 = { by lemma 16 } 32.26/32.42 join(complement(a), complement(ifeq(join(b, complement(meet(join(b, a), join(a, meet(complement(a), b))))), one, complement(complement(join(a, meet(b, complement(a))))), b))) 32.26/32.42 = { by axiom 10 (commutativity_of_join) } 32.26/32.42 join(complement(a), complement(ifeq(join(b, complement(meet(join(a, b), join(a, meet(complement(a), b))))), one, complement(complement(join(a, meet(b, complement(a))))), b))) 32.26/32.42 = { by axiom 9 (commutativity_of_meet) } 32.26/32.42 join(complement(a), complement(ifeq(join(b, complement(meet(join(a, b), join(a, meet(b, complement(a)))))), one, complement(complement(join(a, meet(b, complement(a))))), b))) 32.26/32.42 = { by lemma 19 } 32.26/32.42 join(complement(a), complement(ifeq(join(b, complement(join(a, meet(b, complement(a))))), one, complement(complement(join(a, meet(b, complement(a))))), b))) 32.26/32.42 = { by lemma 21 } 32.26/32.42 join(complement(a), complement(ifeq(join(b, meet(complement(join(a, meet(b, complement(a)))), one)), one, complement(complement(join(a, meet(b, complement(a))))), b))) 32.26/32.42 = { by lemma 25 } 32.26/32.42 join(complement(a), complement(ifeq(join(b, meet(complement(join(a, meet(b, complement(a)))), complement(zero))), one, complement(complement(join(a, meet(b, complement(a))))), b))) 32.26/32.42 = { by lemma 31 } 32.26/32.42 join(complement(a), complement(ifeq(join(b, meet(complement(join(a, meet(b, complement(a)))), complement(meet(b, complement(join(a, meet(b, complement(a)))))))), one, complement(complement(join(a, meet(b, complement(a))))), b))) 32.26/32.42 = { by axiom 10 (commutativity_of_join) } 32.26/32.42 join(complement(a), complement(ifeq(join(meet(complement(join(a, meet(b, complement(a)))), complement(meet(b, complement(join(a, meet(b, complement(a))))))), b), one, complement(complement(join(a, meet(b, complement(a))))), b))) 32.26/32.42 = { by lemma 21 } 32.26/32.42 join(complement(a), complement(ifeq(join(meet(complement(join(a, meet(b, complement(a)))), complement(meet(b, complement(join(a, meet(b, complement(a))))))), b), one, complement(meet(complement(join(a, meet(b, complement(a)))), one)), b))) 32.26/32.42 = { by lemma 25 } 32.26/32.42 join(complement(a), complement(ifeq(join(meet(complement(join(a, meet(b, complement(a)))), complement(meet(b, complement(join(a, meet(b, complement(a))))))), b), one, complement(meet(complement(join(a, meet(b, complement(a)))), complement(zero))), b))) 32.26/32.42 = { by lemma 31 } 32.26/32.42 join(complement(a), complement(ifeq(join(meet(complement(join(a, meet(b, complement(a)))), complement(meet(b, complement(join(a, meet(b, complement(a))))))), b), one, complement(meet(complement(join(a, meet(b, complement(a)))), complement(meet(b, complement(join(a, meet(b, complement(a)))))))), b))) 32.26/32.42 = { by axiom 7 (ifeq_axiom) } 32.26/32.42 join(complement(a), complement(ifeq(join(meet(complement(join(a, meet(b, complement(a)))), complement(meet(b, complement(join(a, meet(b, complement(a))))))), b), one, ifeq(zero, zero, complement(meet(complement(join(a, meet(b, complement(a)))), complement(meet(b, complement(join(a, meet(b, complement(a)))))))), b), b))) 32.26/32.42 = { by axiom 3 (complement_meet) } 32.26/32.42 join(complement(a), complement(ifeq(join(meet(complement(join(a, meet(b, complement(a)))), complement(meet(b, complement(join(a, meet(b, complement(a))))))), b), one, ifeq(meet(meet(b, complement(join(a, meet(b, complement(a))))), complement(meet(b, complement(join(a, meet(b, complement(a))))))), zero, complement(meet(complement(join(a, meet(b, complement(a)))), complement(meet(b, complement(join(a, meet(b, complement(a)))))))), b), b))) 32.26/32.42 = { by axiom 4 (associativity_of_meet) } 32.26/32.42 join(complement(a), complement(ifeq(join(meet(complement(join(a, meet(b, complement(a)))), complement(meet(b, complement(join(a, meet(b, complement(a))))))), b), one, ifeq(meet(b, meet(complement(join(a, meet(b, complement(a)))), complement(meet(b, complement(join(a, meet(b, complement(a)))))))), zero, complement(meet(complement(join(a, meet(b, complement(a)))), complement(meet(b, complement(join(a, meet(b, complement(a)))))))), b), b))) 32.26/32.42 = { by lemma 14 } 32.26/32.42 join(complement(a), complement(b)) 32.26/32.42 = { by axiom 10 (commutativity_of_join) } 32.26/32.42 join(complement(b), complement(a)) 32.26/32.42 % SZS output end Proof 32.26/32.42 32.26/32.42 RESULT: Unsatisfiable (the axioms are contradictory). 32.26/32.43 EOF