0.07/0.12 % Problem : theBenchmark.p : TPTP v0.0.0. Released v0.0.0. 0.07/0.12 % Command : twee %s --tstp --casc --quiet --explain-encoding --conditional-encoding if --smaller --drop-non-horn 0.13/0.34 % Computer : n003.cluster.edu 0.13/0.34 % Model : x86_64 x86_64 0.13/0.34 % CPU : Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz 0.13/0.34 % Memory : 8042.1875MB 0.13/0.34 % OS : Linux 3.10.0-693.el7.x86_64 0.13/0.34 % CPULimit : 180 0.13/0.34 % DateTime : Thu Aug 29 14:53:17 EDT 2019 0.13/0.34 % CPUTime : 45.01/45.21 % SZS status Theorem 45.01/45.21 45.01/45.21 % SZS output start Proof 45.01/45.21 Take the following subset of the input axioms: 45.18/45.38 fof(and_1, axiom, ![X, Y]: is_a_theorem(implies(and(X, Y), X)) <=> and_1). 45.18/45.38 fof(and_2, axiom, and_2 <=> ![X, Y]: is_a_theorem(implies(and(X, Y), Y))). 45.18/45.38 fof(and_3, axiom, ![X, Y]: is_a_theorem(implies(X, implies(Y, and(X, Y)))) <=> and_3). 45.18/45.38 fof(axiom_M, axiom, axiom_M <=> ![X]: is_a_theorem(implies(necessarily(X), X))). 45.18/45.38 fof(axiom_m1, axiom, axiom_m1 <=> ![X, Y]: is_a_theorem(strict_implies(and(X, Y), and(Y, X)))). 45.18/45.38 fof(hilbert_and_1, axiom, and_1). 45.18/45.38 fof(hilbert_and_2, axiom, and_2). 45.18/45.38 fof(hilbert_and_3, axiom, and_3). 45.18/45.38 fof(hilbert_implies_1, axiom, implies_1). 45.18/45.38 fof(hilbert_implies_2, axiom, implies_2). 45.18/45.38 fof(hilbert_modus_ponens, axiom, modus_ponens). 45.18/45.38 fof(hilbert_modus_tollens, axiom, modus_tollens). 45.18/45.38 fof(hilbert_op_equiv, axiom, op_equiv). 45.18/45.38 fof(hilbert_op_implies_and, axiom, op_implies_and). 45.18/45.38 fof(hilbert_op_or, axiom, op_or). 45.18/45.38 fof(hilbert_or_1, axiom, or_1). 45.18/45.38 fof(hilbert_or_2, axiom, or_2). 45.18/45.38 fof(hilbert_or_3, axiom, or_3). 45.18/45.38 fof(implies_1, axiom, implies_1 <=> ![X, Y]: is_a_theorem(implies(X, implies(Y, X)))). 45.18/45.38 fof(implies_2, axiom, implies_2 <=> ![X, Y]: is_a_theorem(implies(implies(X, implies(X, Y)), implies(X, Y)))). 45.18/45.38 fof(km5_axiom_M, axiom, axiom_M). 45.18/45.38 fof(km5_necessitation, axiom, necessitation). 45.18/45.38 fof(km5_op_possibly, axiom, op_possibly). 45.18/45.38 fof(kn1, axiom, ![P]: is_a_theorem(implies(P, and(P, P))) <=> kn1). 45.18/45.38 fof(modus_ponens, axiom, modus_ponens <=> ![X, Y]: ((is_a_theorem(X) & is_a_theorem(implies(X, Y))) => is_a_theorem(Y))). 45.18/45.38 fof(modus_tollens, axiom, ![X, Y]: is_a_theorem(implies(implies(not(Y), not(X)), implies(X, Y))) <=> modus_tollens). 45.18/45.38 fof(necessitation, axiom, necessitation <=> ![X]: (is_a_theorem(necessarily(X)) <= is_a_theorem(X))). 45.18/45.38 fof(op_and, axiom, ![X, Y]: not(or(not(X), not(Y)))=and(X, Y) <= op_and). 45.18/45.38 fof(op_equiv, axiom, op_equiv => ![X, Y]: equiv(X, Y)=and(implies(X, Y), implies(Y, X))). 45.18/45.38 fof(op_implies_and, axiom, op_implies_and => ![X, Y]: implies(X, Y)=not(and(X, not(Y)))). 45.18/45.38 fof(op_or, axiom, op_or => ![X, Y]: or(X, Y)=not(and(not(X), not(Y)))). 45.18/45.38 fof(op_possibly, axiom, ![X]: not(necessarily(not(X)))=possibly(X) <= op_possibly). 45.18/45.38 fof(op_strict_implies, axiom, ![X, Y]: necessarily(implies(X, Y))=strict_implies(X, Y) <= op_strict_implies). 45.18/45.38 fof(or_1, axiom, or_1 <=> ![X, Y]: is_a_theorem(implies(X, or(X, Y)))). 45.18/45.38 fof(or_2, axiom, or_2 <=> ![X, Y]: is_a_theorem(implies(Y, or(X, Y)))). 45.18/45.38 fof(or_3, axiom, ![X, Y, Z]: is_a_theorem(implies(implies(X, Z), implies(implies(Y, Z), implies(or(X, Y), Z)))) <=> or_3). 45.18/45.38 fof(s1_0_axiom_m1, conjecture, axiom_m1). 45.18/45.38 fof(s1_0_op_strict_implies, axiom, op_strict_implies). 45.18/45.38 fof(substitution_of_equivalents, axiom, substitution_of_equivalents <=> ![X, Y]: (is_a_theorem(equiv(X, Y)) => X=Y)). 45.18/45.38 fof(substitution_of_equivalents, axiom, substitution_of_equivalents). 45.18/45.38 45.18/45.38 Now clausify the problem and encode Horn clauses using encoding 3 of 45.18/45.38 http://www.cse.chalmers.se/~nicsma/papers/horn.pdf. 45.18/45.38 We repeatedly replace C & s=t => u=v by the two clauses: 45.18/45.38 fresh(y, y, x1...xn) = u 45.18/45.38 C => fresh(s, t, x1...xn) = v 45.18/45.38 where fresh is a fresh function symbol and x1..xn are the free 45.18/45.38 variables of u and v. 45.18/45.38 A predicate p(X) is encoded as p(X)=true (this is sound, because the 45.18/45.38 input problem has no model of domain size 1). 45.18/45.38 45.18/45.38 The encoding turns the above axioms into the following unit equations and goals: 45.18/45.38 45.18/45.38 Axiom 1 (and_1_1): fresh107(X, X, Y, Z) = true. 45.18/45.38 Axiom 2 (and_2_1): fresh105(X, X, Y, Z) = true. 45.18/45.38 Axiom 3 (and_3_1): fresh103(X, X, Y, Z) = true. 45.18/45.38 Axiom 4 (axiom_M_1): fresh93(X, X, Y) = true. 45.18/45.38 Axiom 5 (axiom_m1): fresh92(X, X) = true. 45.18/45.38 Axiom 6 (implies_1_1): fresh51(X, X, Y, Z) = true. 45.18/45.38 Axiom 7 (implies_2_1): fresh49(X, X, Y, Z) = true. 45.18/45.38 Axiom 8 (modus_ponens_2): fresh40(X, X, Y, Z) = is_a_theorem(Z). 45.18/45.38 Axiom 9 (modus_ponens_2): fresh116(X, X, Y) = true. 45.18/45.38 Axiom 10 (modus_ponens_2): fresh115(X, X, Y, Z) = fresh116(is_a_theorem(Y), true, Z). 45.18/45.38 Axiom 11 (modus_tollens_1): fresh35(X, X, Y, Z) = true. 45.18/45.38 Axiom 12 (necessitation_1): fresh34(X, X, Y) = is_a_theorem(necessarily(Y)). 45.18/45.38 Axiom 13 (necessitation_1): fresh33(X, X, Y) = true. 45.18/45.38 Axiom 14 (op_equiv): fresh30(X, X, Y, Z) = equiv(Y, Z). 45.18/45.38 Axiom 15 (op_implies_and): fresh29(X, X, Y, Z) = implies(Y, Z). 45.18/45.38 Axiom 16 (op_or): fresh26(X, X, Y, Z) = or(Y, Z). 45.18/45.38 Axiom 17 (op_possibly): fresh25(X, X, Y) = possibly(Y). 45.18/45.38 Axiom 18 (op_strict_implies): fresh23(X, X, Y, Z) = strict_implies(Y, Z). 45.18/45.38 Axiom 19 (or_1_1): fresh21(X, X, Y, Z) = true. 45.18/45.38 Axiom 20 (or_2_1): fresh19(X, X, Y, Z) = true. 45.18/45.38 Axiom 21 (or_3_1): fresh17(X, X, Y, Z, W) = true. 45.18/45.38 Axiom 22 (substitution_of_equivalents_2): fresh4(X, X, Y, Z) = Y. 45.18/45.38 Axiom 23 (substitution_of_equivalents_2): fresh3(X, X, Y, Z) = Z. 45.18/45.38 Axiom 24 (and_3_1): fresh103(and_3, true, X, Y) = is_a_theorem(implies(X, implies(Y, and(X, Y)))). 45.18/45.38 Axiom 25 (substitution_of_equivalents_2): fresh4(substitution_of_equivalents, true, X, Y) = fresh3(is_a_theorem(equiv(X, Y)), true, X, Y). 45.18/45.38 Axiom 26 (modus_ponens_2): fresh115(modus_ponens, true, X, Y) = fresh40(is_a_theorem(implies(X, Y)), true, X, Y). 45.18/45.38 Axiom 27 (kn1_1): fresh45(kn1, true, X) = is_a_theorem(implies(X, and(X, X))). 45.18/45.38 Axiom 28 (and_1_1): fresh107(and_1, true, X, Y) = is_a_theorem(implies(and(X, Y), X)). 45.18/45.38 Axiom 29 (and_2_1): fresh105(and_2, true, X, Y) = is_a_theorem(implies(and(X, Y), Y)). 45.18/45.38 Axiom 30 (or_2_1): fresh19(or_2, true, X, Y) = is_a_theorem(implies(Y, or(X, Y))). 45.18/45.38 Axiom 31 (implies_2_1): fresh49(implies_2, true, X, Y) = is_a_theorem(implies(implies(X, implies(X, Y)), implies(X, Y))). 45.18/45.38 Axiom 32 (or_3_1): fresh17(or_3, true, X, Y, Z) = is_a_theorem(implies(implies(X, Z), implies(implies(Y, Z), implies(or(X, Y), Z)))). 45.18/45.38 Axiom 33 (modus_tollens_1): fresh35(modus_tollens, true, X, Y) = is_a_theorem(implies(implies(not(Y), not(X)), implies(X, Y))). 45.18/45.38 Axiom 34 (implies_1_1): fresh51(implies_1, true, X, Y) = is_a_theorem(implies(X, implies(Y, X))). 45.18/45.38 Axiom 35 (or_1_1): fresh21(or_1, true, X, Y) = is_a_theorem(implies(X, or(X, Y))). 45.18/45.38 Axiom 36 (op_and): fresh31(op_and, true, X, Y) = not(or(not(X), not(Y))). 45.18/45.38 Axiom 37 (op_or): fresh26(op_or, true, X, Y) = not(and(not(X), not(Y))). 45.18/45.38 Axiom 38 (op_equiv): fresh30(op_equiv, true, X, Y) = and(implies(X, Y), implies(Y, X)). 45.18/45.38 Axiom 39 (op_implies_and): fresh29(op_implies_and, true, X, Y) = not(and(X, not(Y))). 45.18/45.38 Axiom 40 (hilbert_modus_tollens): modus_tollens = true. 45.18/45.38 Axiom 41 (hilbert_and_2): and_2 = true. 45.18/45.38 Axiom 42 (hilbert_and_1): and_1 = true. 45.18/45.38 Axiom 43 (substitution_of_equivalents): substitution_of_equivalents = true. 45.18/45.38 Axiom 44 (hilbert_and_3): and_3 = true. 45.18/45.38 Axiom 45 (hilbert_implies_1): implies_1 = true. 45.18/45.38 Axiom 46 (hilbert_or_1): or_1 = true. 45.18/45.38 Axiom 47 (hilbert_or_2): or_2 = true. 45.18/45.38 Axiom 48 (hilbert_modus_ponens): modus_ponens = true. 45.18/45.38 Axiom 49 (hilbert_or_3): or_3 = true. 45.18/45.38 Axiom 50 (hilbert_implies_2): implies_2 = true. 45.18/45.38 Axiom 51 (hilbert_op_equiv): op_equiv = true. 45.18/45.38 Axiom 52 (hilbert_op_implies_and): op_implies_and = true. 45.18/45.38 Axiom 53 (hilbert_op_or): op_or = true. 45.18/45.38 Axiom 54 (axiom_m1_1): fresh89(axiom_m1, true, X, Y) = is_a_theorem(strict_implies(and(X, Y), and(Y, X))). 45.18/45.38 Axiom 55 (axiom_m1): fresh92(is_a_theorem(strict_implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) = axiom_m1. 45.18/45.38 Axiom 56 (necessitation_1): fresh34(necessitation, true, X) = fresh33(is_a_theorem(X), true, X). 45.18/45.38 Axiom 57 (axiom_M_1): fresh93(axiom_M, true, X) = is_a_theorem(implies(necessarily(X), X)). 45.18/45.38 Axiom 58 (op_strict_implies): fresh23(op_strict_implies, true, X, Y) = necessarily(implies(X, Y)). 45.18/45.38 Axiom 59 (op_possibly): fresh25(op_possibly, true, X) = not(necessarily(not(X))). 45.18/45.38 Axiom 60 (km5_axiom_M): axiom_M = true. 45.18/45.38 Axiom 61 (km5_necessitation): necessitation = true. 45.18/45.38 Axiom 62 (km5_op_possibly): op_possibly = true. 45.18/45.41 Axiom 63 (s1_0_op_strict_implies): op_strict_implies = true. 45.18/45.41 45.18/45.41 Lemma 64: not(and(X, not(Y))) = implies(X, Y). 45.18/45.41 Proof: 45.18/45.41 not(and(X, not(Y))) 45.18/45.41 = { by axiom 39 (op_implies_and) } 45.18/45.41 fresh29(op_implies_and, true, X, Y) 45.18/45.41 = { by axiom 52 (hilbert_op_implies_and) } 45.18/45.41 fresh29(true, true, X, Y) 45.18/45.41 = { by axiom 15 (op_implies_and) } 45.18/45.41 implies(X, Y) 45.18/45.41 45.18/45.41 Lemma 65: fresh3(is_a_theorem(equiv(X, Y)), true, X, Y) = X. 45.18/45.41 Proof: 45.18/45.41 fresh3(is_a_theorem(equiv(X, Y)), true, X, Y) 45.18/45.41 = { by axiom 25 (substitution_of_equivalents_2) } 45.18/45.41 fresh4(substitution_of_equivalents, true, X, Y) 45.18/45.41 = { by axiom 43 (substitution_of_equivalents) } 45.18/45.41 fresh4(true, true, X, Y) 45.18/45.41 = { by axiom 22 (substitution_of_equivalents_2) } 45.18/45.41 X 45.18/45.41 45.18/45.41 Lemma 66: and(implies(X, Y), implies(Y, X)) = equiv(X, Y). 45.18/45.41 Proof: 45.18/45.41 and(implies(X, Y), implies(Y, X)) 45.18/45.41 = { by axiom 38 (op_equiv) } 45.18/45.41 fresh30(op_equiv, true, X, Y) 45.18/45.41 = { by axiom 51 (hilbert_op_equiv) } 45.18/45.41 fresh30(true, true, X, Y) 45.18/45.41 = { by axiom 14 (op_equiv) } 45.18/45.41 equiv(X, Y) 45.18/45.41 45.18/45.41 Lemma 67: fresh40(is_a_theorem(implies(X, Y)), true, X, Y) = fresh116(is_a_theorem(X), true, Y). 45.18/45.41 Proof: 45.18/45.41 fresh40(is_a_theorem(implies(X, Y)), true, X, Y) 45.18/45.41 = { by axiom 26 (modus_ponens_2) } 45.18/45.41 fresh115(modus_ponens, true, X, Y) 45.18/45.41 = { by axiom 48 (hilbert_modus_ponens) } 45.18/45.41 fresh115(true, true, X, Y) 45.18/45.41 = { by axiom 10 (modus_ponens_2) } 45.18/45.41 fresh116(is_a_theorem(X), true, Y) 45.18/45.41 45.18/45.41 Lemma 68: is_a_theorem(implies(X, implies(Y, and(X, Y)))) = true. 45.18/45.41 Proof: 45.18/45.41 is_a_theorem(implies(X, implies(Y, and(X, Y)))) 45.18/45.41 = { by axiom 24 (and_3_1) } 45.18/45.41 fresh103(and_3, true, X, Y) 45.18/45.41 = { by axiom 44 (hilbert_and_3) } 45.18/45.41 fresh103(true, true, X, Y) 45.18/45.41 = { by axiom 3 (and_3_1) } 45.18/45.41 true 45.18/45.41 45.18/45.41 Lemma 69: fresh116(is_a_theorem(X), true, implies(Y, and(X, Y))) = is_a_theorem(implies(Y, and(X, Y))). 45.18/45.41 Proof: 45.18/45.41 fresh116(is_a_theorem(X), true, implies(Y, and(X, Y))) 45.18/45.41 = { by lemma 67 } 45.18/45.41 fresh40(is_a_theorem(implies(X, implies(Y, and(X, Y)))), true, X, implies(Y, and(X, Y))) 45.18/45.41 = { by lemma 68 } 45.18/45.41 fresh40(true, true, X, implies(Y, and(X, Y))) 45.18/45.41 = { by axiom 8 (modus_ponens_2) } 45.18/45.41 is_a_theorem(implies(Y, and(X, Y))) 45.18/45.41 45.18/45.41 Lemma 70: fresh116(is_a_theorem(implies(X, implies(X, Y))), true, implies(X, Y)) = is_a_theorem(implies(X, Y)). 45.18/45.41 Proof: 45.18/45.41 fresh116(is_a_theorem(implies(X, implies(X, Y))), true, implies(X, Y)) 45.18/45.41 = { by lemma 67 } 45.18/45.41 fresh40(is_a_theorem(implies(implies(X, implies(X, Y)), implies(X, Y))), true, implies(X, implies(X, Y)), implies(X, Y)) 45.18/45.41 = { by axiom 31 (implies_2_1) } 45.18/45.41 fresh40(fresh49(implies_2, true, X, Y), true, implies(X, implies(X, Y)), implies(X, Y)) 45.18/45.41 = { by axiom 50 (hilbert_implies_2) } 45.18/45.41 fresh40(fresh49(true, true, X, Y), true, implies(X, implies(X, Y)), implies(X, Y)) 45.18/45.41 = { by axiom 7 (implies_2_1) } 45.18/45.41 fresh40(true, true, implies(X, implies(X, Y)), implies(X, Y)) 45.18/45.41 = { by axiom 8 (modus_ponens_2) } 45.18/45.41 is_a_theorem(implies(X, Y)) 45.18/45.41 45.18/45.41 Lemma 71: is_a_theorem(implies(X, X)) = true. 45.18/45.41 Proof: 45.18/45.41 is_a_theorem(implies(X, X)) 45.18/45.41 = { by lemma 70 } 45.18/45.41 fresh116(is_a_theorem(implies(X, implies(X, X))), true, implies(X, X)) 45.18/45.41 = { by axiom 34 (implies_1_1) } 45.18/45.41 fresh116(fresh51(implies_1, true, X, X), true, implies(X, X)) 45.18/45.41 = { by axiom 45 (hilbert_implies_1) } 45.18/45.41 fresh116(fresh51(true, true, X, X), true, implies(X, X)) 45.18/45.41 = { by axiom 6 (implies_1_1) } 45.18/45.41 fresh116(true, true, implies(X, X)) 45.18/45.41 = { by axiom 9 (modus_ponens_2) } 45.18/45.42 true 45.18/45.42 45.18/45.42 Lemma 72: or(Y, implies(X, X)) = implies(X, X). 45.18/45.42 Proof: 45.18/45.42 or(Y, implies(X, X)) 45.18/45.42 = { by axiom 23 (substitution_of_equivalents_2) } 45.18/45.42 fresh3(true, true, implies(X, X), or(Y, implies(X, X))) 45.18/45.42 = { by axiom 9 (modus_ponens_2) } 45.18/45.42 fresh3(fresh116(true, true, and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X)))), true, implies(X, X), or(Y, implies(X, X))) 45.18/45.42 = { by axiom 9 (modus_ponens_2) } 45.18/45.42 fresh3(fresh116(fresh116(true, true, implies(or(Y, implies(X, X)), implies(X, X))), true, and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X)))), true, implies(X, X), or(Y, implies(X, X))) 45.18/45.42 = { by lemma 71 } 45.18/45.42 fresh3(fresh116(fresh116(is_a_theorem(implies(X, X)), true, implies(or(Y, implies(X, X)), implies(X, X))), true, and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X)))), true, implies(X, X), or(Y, implies(X, X))) 45.18/45.42 = { by axiom 10 (modus_ponens_2) } 45.18/45.42 fresh3(fresh116(fresh115(true, true, implies(X, X), implies(or(Y, implies(X, X)), implies(X, X))), true, and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X)))), true, implies(X, X), or(Y, implies(X, X))) 45.18/45.42 = { by axiom 48 (hilbert_modus_ponens) } 45.18/45.42 fresh3(fresh116(fresh115(modus_ponens, true, implies(X, X), implies(or(Y, implies(X, X)), implies(X, X))), true, and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X)))), true, implies(X, X), or(Y, implies(X, X))) 45.18/45.42 = { by axiom 26 (modus_ponens_2) } 45.18/45.42 fresh3(fresh116(fresh40(is_a_theorem(implies(implies(X, X), implies(or(Y, implies(X, X)), implies(X, X)))), true, implies(X, X), implies(or(Y, implies(X, X)), implies(X, X))), true, and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X)))), true, implies(X, X), or(Y, implies(X, X))) 45.18/45.42 = { by axiom 34 (implies_1_1) } 45.18/45.42 fresh3(fresh116(fresh40(fresh51(implies_1, true, implies(X, X), or(Y, implies(X, X))), true, implies(X, X), implies(or(Y, implies(X, X)), implies(X, X))), true, and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X)))), true, implies(X, X), or(Y, implies(X, X))) 45.18/45.42 = { by axiom 45 (hilbert_implies_1) } 45.18/45.42 fresh3(fresh116(fresh40(fresh51(true, true, implies(X, X), or(Y, implies(X, X))), true, implies(X, X), implies(or(Y, implies(X, X)), implies(X, X))), true, and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X)))), true, implies(X, X), or(Y, implies(X, X))) 45.18/45.42 = { by axiom 6 (implies_1_1) } 45.18/45.42 fresh3(fresh116(fresh40(true, true, implies(X, X), implies(or(Y, implies(X, X)), implies(X, X))), true, and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X)))), true, implies(X, X), or(Y, implies(X, X))) 45.18/45.42 = { by axiom 8 (modus_ponens_2) } 45.18/45.42 fresh3(fresh116(is_a_theorem(implies(or(Y, implies(X, X)), implies(X, X))), true, and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X)))), true, implies(X, X), or(Y, implies(X, X))) 45.18/45.42 = { by lemma 67 } 45.25/45.42 fresh3(fresh40(is_a_theorem(implies(implies(or(Y, implies(X, X)), implies(X, X)), and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X))))), true, implies(or(Y, implies(X, X)), implies(X, X)), and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X)))), true, implies(X, X), or(Y, implies(X, X))) 45.25/45.42 = { by lemma 69 } 45.25/45.42 fresh3(fresh40(fresh116(is_a_theorem(implies(implies(X, X), or(Y, implies(X, X)))), true, implies(implies(or(Y, implies(X, X)), implies(X, X)), and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X))))), true, implies(or(Y, implies(X, X)), implies(X, X)), and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X)))), true, implies(X, X), or(Y, implies(X, X))) 45.25/45.42 = { by axiom 30 (or_2_1) } 45.25/45.42 fresh3(fresh40(fresh116(fresh19(or_2, true, Y, implies(X, X)), true, implies(implies(or(Y, implies(X, X)), implies(X, X)), and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X))))), true, implies(or(Y, implies(X, X)), implies(X, X)), and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X)))), true, implies(X, X), or(Y, implies(X, X))) 45.25/45.42 = { by axiom 47 (hilbert_or_2) } 45.25/45.42 fresh3(fresh40(fresh116(fresh19(true, true, Y, implies(X, X)), true, implies(implies(or(Y, implies(X, X)), implies(X, X)), and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X))))), true, implies(or(Y, implies(X, X)), implies(X, X)), and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X)))), true, implies(X, X), or(Y, implies(X, X))) 45.25/45.42 = { by axiom 20 (or_2_1) } 45.25/45.42 fresh3(fresh40(fresh116(true, true, implies(implies(or(Y, implies(X, X)), implies(X, X)), and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X))))), true, implies(or(Y, implies(X, X)), implies(X, X)), and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X)))), true, implies(X, X), or(Y, implies(X, X))) 45.25/45.42 = { by axiom 9 (modus_ponens_2) } 45.25/45.42 fresh3(fresh40(true, true, implies(or(Y, implies(X, X)), implies(X, X)), and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X)))), true, implies(X, X), or(Y, implies(X, X))) 45.25/45.42 = { by axiom 8 (modus_ponens_2) } 45.25/45.42 fresh3(is_a_theorem(and(implies(implies(X, X), or(Y, implies(X, X))), implies(or(Y, implies(X, X)), implies(X, X)))), true, implies(X, X), or(Y, implies(X, X))) 45.25/45.42 = { by lemma 66 } 45.25/45.42 fresh3(is_a_theorem(equiv(implies(X, X), or(Y, implies(X, X)))), true, implies(X, X), or(Y, implies(X, X))) 45.25/45.42 = { by lemma 65 } 45.25/45.42 implies(X, X) 45.25/45.42 45.25/45.42 Lemma 73: implies(not(X), Y) = or(X, Y). 45.25/45.42 Proof: 45.25/45.42 implies(not(X), Y) 45.25/45.42 = { by lemma 64 } 45.25/45.42 not(and(not(X), not(Y))) 45.25/45.42 = { by axiom 37 (op_or) } 45.25/45.42 fresh26(op_or, true, X, Y) 45.25/45.42 = { by axiom 53 (hilbert_op_or) } 45.25/45.42 fresh26(true, true, X, Y) 45.25/45.42 = { by axiom 16 (op_or) } 45.25/45.42 or(X, Y) 45.25/45.42 45.25/45.42 Lemma 74: and(implies(X, not(Y)), or(Y, X)) = equiv(X, not(Y)). 45.25/45.42 Proof: 45.25/45.42 and(implies(X, not(Y)), or(Y, X)) 45.25/45.42 = { by lemma 73 } 45.25/45.42 and(implies(X, not(Y)), implies(not(Y), X)) 45.25/45.42 = { by axiom 38 (op_equiv) } 45.25/45.42 fresh30(op_equiv, true, X, not(Y)) 45.25/45.42 = { by axiom 51 (hilbert_op_equiv) } 45.25/45.42 fresh30(true, true, X, not(Y)) 45.25/45.42 = { by axiom 14 (op_equiv) } 45.25/45.42 equiv(X, not(Y)) 45.25/45.42 45.25/45.42 Lemma 75: is_a_theorem(implies(and(X, Y), X)) = true. 45.25/45.42 Proof: 45.25/45.42 is_a_theorem(implies(and(X, Y), X)) 45.25/45.42 = { by axiom 28 (and_1_1) } 45.25/45.42 fresh107(and_1, true, X, Y) 45.25/45.42 = { by axiom 42 (hilbert_and_1) } 45.25/45.42 fresh107(true, true, X, Y) 45.25/45.42 = { by axiom 1 (and_1_1) } 45.25/45.43 true 45.25/45.43 45.25/45.43 Lemma 76: is_a_theorem(or(implies(X, X), Y)) = true. 45.25/45.43 Proof: 45.25/45.43 is_a_theorem(or(implies(X, X), Y)) 45.25/45.43 = { by axiom 8 (modus_ponens_2) } 45.25/45.43 fresh40(true, true, implies(X, X), or(implies(X, X), Y)) 45.25/45.43 = { by axiom 19 (or_1_1) } 45.25/45.43 fresh40(fresh21(true, true, implies(X, X), Y), true, implies(X, X), or(implies(X, X), Y)) 45.25/45.43 = { by axiom 46 (hilbert_or_1) } 45.25/45.43 fresh40(fresh21(or_1, true, implies(X, X), Y), true, implies(X, X), or(implies(X, X), Y)) 45.25/45.43 = { by axiom 35 (or_1_1) } 45.25/45.43 fresh40(is_a_theorem(implies(implies(X, X), or(implies(X, X), Y))), true, implies(X, X), or(implies(X, X), Y)) 45.25/45.43 = { by axiom 26 (modus_ponens_2) } 45.25/45.43 fresh115(modus_ponens, true, implies(X, X), or(implies(X, X), Y)) 45.25/45.43 = { by axiom 48 (hilbert_modus_ponens) } 45.25/45.43 fresh115(true, true, implies(X, X), or(implies(X, X), Y)) 45.25/45.43 = { by axiom 10 (modus_ponens_2) } 45.25/45.43 fresh116(is_a_theorem(implies(X, X)), true, or(implies(X, X), Y)) 45.25/45.43 = { by lemma 71 } 45.25/45.43 fresh116(true, true, or(implies(X, X), Y)) 45.25/45.43 = { by axiom 9 (modus_ponens_2) } 45.25/45.43 true 45.25/45.43 45.25/45.43 Lemma 77: not(not(implies(X, X))) = possibly(implies(X, X)). 45.25/45.43 Proof: 45.25/45.43 not(not(implies(X, X))) 45.25/45.43 = { by axiom 23 (substitution_of_equivalents_2) } 45.25/45.43 not(fresh3(true, true, necessarily(not(implies(X, X))), not(implies(X, X)))) 45.25/45.43 = { by axiom 9 (modus_ponens_2) } 45.25/45.43 not(fresh3(fresh116(true, true, and(implies(necessarily(not(implies(X, X))), not(implies(X, X))), or(implies(X, X), necessarily(not(implies(X, X)))))), true, necessarily(not(implies(X, X))), not(implies(X, X)))) 45.25/45.43 = { by lemma 76 } 45.25/45.43 not(fresh3(fresh116(is_a_theorem(or(implies(X, X), necessarily(not(implies(X, X))))), true, and(implies(necessarily(not(implies(X, X))), not(implies(X, X))), or(implies(X, X), necessarily(not(implies(X, X)))))), true, necessarily(not(implies(X, X))), not(implies(X, X)))) 45.25/45.43 = { by lemma 67 } 45.25/45.43 not(fresh3(fresh40(is_a_theorem(implies(or(implies(X, X), necessarily(not(implies(X, X)))), and(implies(necessarily(not(implies(X, X))), not(implies(X, X))), or(implies(X, X), necessarily(not(implies(X, X))))))), true, or(implies(X, X), necessarily(not(implies(X, X)))), and(implies(necessarily(not(implies(X, X))), not(implies(X, X))), or(implies(X, X), necessarily(not(implies(X, X)))))), true, necessarily(not(implies(X, X))), not(implies(X, X)))) 45.25/45.43 = { by lemma 69 } 45.25/45.43 not(fresh3(fresh40(fresh116(is_a_theorem(implies(necessarily(not(implies(X, X))), not(implies(X, X)))), true, implies(or(implies(X, X), necessarily(not(implies(X, X)))), and(implies(necessarily(not(implies(X, X))), not(implies(X, X))), or(implies(X, X), necessarily(not(implies(X, X))))))), true, or(implies(X, X), necessarily(not(implies(X, X)))), and(implies(necessarily(not(implies(X, X))), not(implies(X, X))), or(implies(X, X), necessarily(not(implies(X, X)))))), true, necessarily(not(implies(X, X))), not(implies(X, X)))) 45.25/45.43 = { by axiom 57 (axiom_M_1) } 45.25/45.43 not(fresh3(fresh40(fresh116(fresh93(axiom_M, true, not(implies(X, X))), true, implies(or(implies(X, X), necessarily(not(implies(X, X)))), and(implies(necessarily(not(implies(X, X))), not(implies(X, X))), or(implies(X, X), necessarily(not(implies(X, X))))))), true, or(implies(X, X), necessarily(not(implies(X, X)))), and(implies(necessarily(not(implies(X, X))), not(implies(X, X))), or(implies(X, X), necessarily(not(implies(X, X)))))), true, necessarily(not(implies(X, X))), not(implies(X, X)))) 45.25/45.43 = { by axiom 60 (km5_axiom_M) } 45.25/45.43 not(fresh3(fresh40(fresh116(fresh93(true, true, not(implies(X, X))), true, implies(or(implies(X, X), necessarily(not(implies(X, X)))), and(implies(necessarily(not(implies(X, X))), not(implies(X, X))), or(implies(X, X), necessarily(not(implies(X, X))))))), true, or(implies(X, X), necessarily(not(implies(X, X)))), and(implies(necessarily(not(implies(X, X))), not(implies(X, X))), or(implies(X, X), necessarily(not(implies(X, X)))))), true, necessarily(not(implies(X, X))), not(implies(X, X)))) 45.25/45.43 = { by axiom 4 (axiom_M_1) } 45.25/45.43 not(fresh3(fresh40(fresh116(true, true, implies(or(implies(X, X), necessarily(not(implies(X, X)))), and(implies(necessarily(not(implies(X, X))), not(implies(X, X))), or(implies(X, X), necessarily(not(implies(X, X))))))), true, or(implies(X, X), necessarily(not(implies(X, X)))), and(implies(necessarily(not(implies(X, X))), not(implies(X, X))), or(implies(X, X), necessarily(not(implies(X, X)))))), true, necessarily(not(implies(X, X))), not(implies(X, X)))) 45.25/45.43 = { by axiom 9 (modus_ponens_2) } 45.25/45.43 not(fresh3(fresh40(true, true, or(implies(X, X), necessarily(not(implies(X, X)))), and(implies(necessarily(not(implies(X, X))), not(implies(X, X))), or(implies(X, X), necessarily(not(implies(X, X)))))), true, necessarily(not(implies(X, X))), not(implies(X, X)))) 45.25/45.43 = { by axiom 8 (modus_ponens_2) } 45.25/45.43 not(fresh3(is_a_theorem(and(implies(necessarily(not(implies(X, X))), not(implies(X, X))), or(implies(X, X), necessarily(not(implies(X, X)))))), true, necessarily(not(implies(X, X))), not(implies(X, X)))) 45.25/45.43 = { by lemma 74 } 45.25/45.43 not(fresh3(is_a_theorem(equiv(necessarily(not(implies(X, X))), not(implies(X, X)))), true, necessarily(not(implies(X, X))), not(implies(X, X)))) 45.25/45.43 = { by lemma 65 } 45.25/45.43 not(necessarily(not(implies(X, X)))) 45.25/45.43 = { by axiom 59 (op_possibly) } 45.25/45.43 fresh25(op_possibly, true, implies(X, X)) 45.25/45.43 = { by axiom 62 (km5_op_possibly) } 45.25/45.43 fresh25(true, true, implies(X, X)) 45.25/45.43 = { by axiom 17 (op_possibly) } 45.25/45.43 possibly(implies(X, X)) 45.25/45.43 45.25/45.43 Lemma 78: or(implies(X, X), Y) = possibly(implies(X, X)). 45.25/45.43 Proof: 45.25/45.43 or(implies(X, X), Y) 45.25/45.43 = { by lemma 73 } 45.25/45.43 implies(not(implies(X, X)), Y) 45.25/45.43 = { by lemma 64 } 45.25/45.43 not(and(not(implies(X, X)), not(Y))) 45.25/45.43 = { by lemma 65 } 45.25/45.43 not(fresh3(is_a_theorem(equiv(and(not(implies(X, X)), not(Y)), not(implies(X, X)))), true, and(not(implies(X, X)), not(Y)), not(implies(X, X)))) 45.25/45.43 = { by lemma 74 } 45.25/45.43 not(fresh3(is_a_theorem(and(implies(and(not(implies(X, X)), not(Y)), not(implies(X, X))), or(implies(X, X), and(not(implies(X, X)), not(Y))))), true, and(not(implies(X, X)), not(Y)), not(implies(X, X)))) 45.25/45.43 = { by axiom 8 (modus_ponens_2) } 45.25/45.43 not(fresh3(fresh40(true, true, or(implies(X, X), and(not(implies(X, X)), not(Y))), and(implies(and(not(implies(X, X)), not(Y)), not(implies(X, X))), or(implies(X, X), and(not(implies(X, X)), not(Y))))), true, and(not(implies(X, X)), not(Y)), not(implies(X, X)))) 45.25/45.43 = { by axiom 9 (modus_ponens_2) } 45.25/45.43 not(fresh3(fresh40(fresh116(true, true, implies(or(implies(X, X), and(not(implies(X, X)), not(Y))), and(implies(and(not(implies(X, X)), not(Y)), not(implies(X, X))), or(implies(X, X), and(not(implies(X, X)), not(Y)))))), true, or(implies(X, X), and(not(implies(X, X)), not(Y))), and(implies(and(not(implies(X, X)), not(Y)), not(implies(X, X))), or(implies(X, X), and(not(implies(X, X)), not(Y))))), true, and(not(implies(X, X)), not(Y)), not(implies(X, X)))) 45.25/45.43 = { by lemma 75 } 45.25/45.43 not(fresh3(fresh40(fresh116(is_a_theorem(implies(and(not(implies(X, X)), not(Y)), not(implies(X, X)))), true, implies(or(implies(X, X), and(not(implies(X, X)), not(Y))), and(implies(and(not(implies(X, X)), not(Y)), not(implies(X, X))), or(implies(X, X), and(not(implies(X, X)), not(Y)))))), true, or(implies(X, X), and(not(implies(X, X)), not(Y))), and(implies(and(not(implies(X, X)), not(Y)), not(implies(X, X))), or(implies(X, X), and(not(implies(X, X)), not(Y))))), true, and(not(implies(X, X)), not(Y)), not(implies(X, X)))) 45.25/45.43 = { by lemma 69 } 45.25/45.43 not(fresh3(fresh40(is_a_theorem(implies(or(implies(X, X), and(not(implies(X, X)), not(Y))), and(implies(and(not(implies(X, X)), not(Y)), not(implies(X, X))), or(implies(X, X), and(not(implies(X, X)), not(Y)))))), true, or(implies(X, X), and(not(implies(X, X)), not(Y))), and(implies(and(not(implies(X, X)), not(Y)), not(implies(X, X))), or(implies(X, X), and(not(implies(X, X)), not(Y))))), true, and(not(implies(X, X)), not(Y)), not(implies(X, X)))) 45.25/45.43 = { by lemma 67 } 45.25/45.43 not(fresh3(fresh116(is_a_theorem(or(implies(X, X), and(not(implies(X, X)), not(Y)))), true, and(implies(and(not(implies(X, X)), not(Y)), not(implies(X, X))), or(implies(X, X), and(not(implies(X, X)), not(Y))))), true, and(not(implies(X, X)), not(Y)), not(implies(X, X)))) 45.25/45.43 = { by lemma 76 } 45.25/45.43 not(fresh3(fresh116(true, true, and(implies(and(not(implies(X, X)), not(Y)), not(implies(X, X))), or(implies(X, X), and(not(implies(X, X)), not(Y))))), true, and(not(implies(X, X)), not(Y)), not(implies(X, X)))) 45.25/45.43 = { by axiom 9 (modus_ponens_2) } 45.25/45.43 not(fresh3(true, true, and(not(implies(X, X)), not(Y)), not(implies(X, X)))) 45.25/45.43 = { by axiom 23 (substitution_of_equivalents_2) } 45.25/45.43 not(not(implies(X, X))) 45.25/45.43 = { by lemma 77 } 45.25/45.43 possibly(implies(X, X)) 45.25/45.43 45.25/45.43 Lemma 79: is_a_theorem(implies(and(X, Y), Y)) = true. 45.25/45.43 Proof: 45.25/45.43 is_a_theorem(implies(and(X, Y), Y)) 45.25/45.43 = { by axiom 29 (and_2_1) } 45.25/45.43 fresh105(and_2, true, X, Y) 45.25/45.43 = { by axiom 41 (hilbert_and_2) } 45.25/45.43 fresh105(true, true, X, Y) 45.25/45.43 = { by axiom 2 (and_2_1) } 45.25/45.44 true 45.25/45.44 45.25/45.44 Lemma 80: and(X, X) = X. 45.25/45.44 Proof: 45.25/45.44 and(X, X) 45.25/45.44 = { by axiom 23 (substitution_of_equivalents_2) } 45.25/45.44 fresh3(true, true, X, and(X, X)) 45.25/45.44 = { by axiom 9 (modus_ponens_2) } 45.25/45.44 fresh3(fresh116(true, true, equiv(X, and(X, X))), true, X, and(X, X)) 45.25/45.44 = { by lemma 79 } 45.25/45.44 fresh3(fresh116(is_a_theorem(implies(and(X, X), X)), true, equiv(X, and(X, X))), true, X, and(X, X)) 45.25/45.44 = { by lemma 67 } 45.25/45.44 fresh3(fresh40(is_a_theorem(implies(implies(and(X, X), X), equiv(X, and(X, X)))), true, implies(and(X, X), X), equiv(X, and(X, X))), true, X, and(X, X)) 45.25/45.44 = { by lemma 66 } 45.25/45.44 fresh3(fresh40(is_a_theorem(implies(implies(and(X, X), X), and(implies(X, and(X, X)), implies(and(X, X), X)))), true, implies(and(X, X), X), equiv(X, and(X, X))), true, X, and(X, X)) 45.25/45.44 = { by lemma 69 } 45.25/45.44 fresh3(fresh40(fresh116(is_a_theorem(implies(X, and(X, X))), true, implies(implies(and(X, X), X), and(implies(X, and(X, X)), implies(and(X, X), X)))), true, implies(and(X, X), X), equiv(X, and(X, X))), true, X, and(X, X)) 45.25/45.44 = { by lemma 70 } 45.25/45.44 fresh3(fresh40(fresh116(fresh116(is_a_theorem(implies(X, implies(X, and(X, X)))), true, implies(X, and(X, X))), true, implies(implies(and(X, X), X), and(implies(X, and(X, X)), implies(and(X, X), X)))), true, implies(and(X, X), X), equiv(X, and(X, X))), true, X, and(X, X)) 45.25/45.44 = { by lemma 68 } 45.25/45.44 fresh3(fresh40(fresh116(fresh116(true, true, implies(X, and(X, X))), true, implies(implies(and(X, X), X), and(implies(X, and(X, X)), implies(and(X, X), X)))), true, implies(and(X, X), X), equiv(X, and(X, X))), true, X, and(X, X)) 45.25/45.44 = { by axiom 9 (modus_ponens_2) } 45.25/45.44 fresh3(fresh40(fresh116(true, true, implies(implies(and(X, X), X), and(implies(X, and(X, X)), implies(and(X, X), X)))), true, implies(and(X, X), X), equiv(X, and(X, X))), true, X, and(X, X)) 45.25/45.44 = { by axiom 9 (modus_ponens_2) } 45.25/45.44 fresh3(fresh40(true, true, implies(and(X, X), X), equiv(X, and(X, X))), true, X, and(X, X)) 45.25/45.44 = { by axiom 8 (modus_ponens_2) } 45.25/45.44 fresh3(is_a_theorem(equiv(X, and(X, X))), true, X, and(X, X)) 45.25/45.44 = { by lemma 65 } 45.25/45.44 X 45.25/45.44 45.25/45.44 Lemma 81: or(X, X) = not(not(X)). 45.25/45.44 Proof: 45.25/45.44 or(X, X) 45.25/45.44 = { by lemma 73 } 45.25/45.44 implies(not(X), X) 45.25/45.44 = { by lemma 64 } 45.25/45.44 not(and(not(X), not(X))) 45.25/45.44 = { by lemma 80 } 45.25/45.44 not(not(X)) 45.25/45.44 45.25/45.44 Lemma 82: possibly(implies(X, X)) = implies(X, X). 45.25/45.44 Proof: 45.25/45.44 possibly(implies(X, X)) 45.25/45.44 = { by lemma 77 } 45.25/45.44 not(not(implies(X, X))) 45.25/45.44 = { by lemma 81 } 45.25/45.44 or(implies(X, X), implies(X, X)) 45.25/45.44 = { by lemma 72 } 45.25/45.44 implies(X, X) 45.25/45.44 45.25/45.44 Lemma 83: and(implies(?, ?), X) = X. 45.25/45.44 Proof: 45.25/45.44 and(implies(?, ?), X) 45.25/45.44 = { by lemma 65 } 45.25/45.44 fresh3(is_a_theorem(equiv(and(implies(?, ?), X), X)), true, and(implies(?, ?), X), X) 45.25/45.44 = { by axiom 8 (modus_ponens_2) } 45.25/45.44 fresh3(fresh40(true, true, implies(X, and(implies(?, ?), X)), equiv(and(implies(?, ?), X), X)), true, and(implies(?, ?), X), X) 45.25/45.44 = { by axiom 9 (modus_ponens_2) } 45.25/45.44 fresh3(fresh40(fresh116(true, true, implies(implies(X, and(implies(?, ?), X)), and(implies(and(implies(?, ?), X), X), implies(X, and(implies(?, ?), X))))), true, implies(X, and(implies(?, ?), X)), equiv(and(implies(?, ?), X), X)), true, and(implies(?, ?), X), X) 45.25/45.44 = { by lemma 79 } 45.25/45.44 fresh3(fresh40(fresh116(is_a_theorem(implies(and(implies(?, ?), X), X)), true, implies(implies(X, and(implies(?, ?), X)), and(implies(and(implies(?, ?), X), X), implies(X, and(implies(?, ?), X))))), true, implies(X, and(implies(?, ?), X)), equiv(and(implies(?, ?), X), X)), true, and(implies(?, ?), X), X) 45.25/45.44 = { by lemma 69 } 45.25/45.44 fresh3(fresh40(is_a_theorem(implies(implies(X, and(implies(?, ?), X)), and(implies(and(implies(?, ?), X), X), implies(X, and(implies(?, ?), X))))), true, implies(X, and(implies(?, ?), X)), equiv(and(implies(?, ?), X), X)), true, and(implies(?, ?), X), X) 45.25/45.44 = { by lemma 66 } 45.25/45.44 fresh3(fresh40(is_a_theorem(implies(implies(X, and(implies(?, ?), X)), equiv(and(implies(?, ?), X), X))), true, implies(X, and(implies(?, ?), X)), equiv(and(implies(?, ?), X), X)), true, and(implies(?, ?), X), X) 45.25/45.44 = { by lemma 67 } 45.25/45.44 fresh3(fresh116(is_a_theorem(implies(X, and(implies(?, ?), X))), true, equiv(and(implies(?, ?), X), X)), true, and(implies(?, ?), X), X) 45.25/45.44 = { by lemma 69 } 45.25/45.44 fresh3(fresh116(fresh116(is_a_theorem(implies(?, ?)), true, implies(X, and(implies(?, ?), X))), true, equiv(and(implies(?, ?), X), X)), true, and(implies(?, ?), X), X) 45.25/45.44 = { by lemma 71 } 45.25/45.44 fresh3(fresh116(fresh116(true, true, implies(X, and(implies(?, ?), X))), true, equiv(and(implies(?, ?), X), X)), true, and(implies(?, ?), X), X) 45.25/45.44 = { by axiom 9 (modus_ponens_2) } 45.25/45.44 fresh3(fresh116(true, true, equiv(and(implies(?, ?), X), X)), true, and(implies(?, ?), X), X) 45.25/45.44 = { by axiom 9 (modus_ponens_2) } 45.25/45.44 fresh3(true, true, and(implies(?, ?), X), X) 45.25/45.44 = { by axiom 23 (substitution_of_equivalents_2) } 45.25/45.44 X 45.25/45.44 45.25/45.44 Lemma 84: or(and(X, not(Y)), Z) = implies(implies(X, Y), Z). 45.25/45.44 Proof: 45.25/45.44 or(and(X, not(Y)), Z) 45.25/45.44 = { by axiom 16 (op_or) } 45.25/45.44 fresh26(true, true, and(X, not(Y)), Z) 45.25/45.44 = { by axiom 53 (hilbert_op_or) } 45.25/45.44 fresh26(op_or, true, and(X, not(Y)), Z) 45.25/45.44 = { by axiom 37 (op_or) } 45.25/45.44 not(and(not(and(X, not(Y))), not(Z))) 45.25/45.44 = { by lemma 64 } 45.25/45.44 not(and(implies(X, Y), not(Z))) 45.25/45.44 = { by lemma 64 } 45.25/45.44 implies(implies(X, Y), Z) 45.25/45.44 45.25/45.44 Lemma 85: implies(or(X, X), Y) = or(not(X), Y). 45.25/45.44 Proof: 45.25/45.44 implies(or(X, X), Y) 45.25/45.44 = { by lemma 73 } 45.25/45.44 implies(implies(not(X), X), Y) 45.25/45.44 = { by lemma 84 } 45.25/45.44 or(and(not(X), not(X)), Y) 45.25/45.44 = { by lemma 80 } 45.25/45.44 or(not(X), Y) 45.25/45.44 45.25/45.44 Lemma 86: fresh116(is_a_theorem(implies(X, Y)), true, or(not(X), Y)) = is_a_theorem(or(not(X), Y)). 45.25/45.44 Proof: 45.25/45.44 fresh116(is_a_theorem(implies(X, Y)), true, or(not(X), Y)) 45.25/45.44 = { by lemma 67 } 45.25/45.44 fresh40(is_a_theorem(implies(implies(X, Y), or(not(X), Y))), true, implies(X, Y), or(not(X), Y)) 45.25/45.44 = { by lemma 85 } 45.25/45.44 fresh40(is_a_theorem(implies(implies(X, Y), implies(or(X, X), Y))), true, implies(X, Y), or(not(X), Y)) 45.25/45.44 = { by lemma 70 } 45.25/45.44 fresh40(fresh116(is_a_theorem(implies(implies(X, Y), implies(implies(X, Y), implies(or(X, X), Y)))), true, implies(implies(X, Y), implies(or(X, X), Y))), true, implies(X, Y), or(not(X), Y)) 45.25/45.44 = { by axiom 32 (or_3_1) } 45.25/45.44 fresh40(fresh116(fresh17(or_3, true, X, X, Y), true, implies(implies(X, Y), implies(or(X, X), Y))), true, implies(X, Y), or(not(X), Y)) 45.25/45.44 = { by axiom 49 (hilbert_or_3) } 45.25/45.44 fresh40(fresh116(fresh17(true, true, X, X, Y), true, implies(implies(X, Y), implies(or(X, X), Y))), true, implies(X, Y), or(not(X), Y)) 45.25/45.44 = { by axiom 21 (or_3_1) } 45.25/45.44 fresh40(fresh116(true, true, implies(implies(X, Y), implies(or(X, X), Y))), true, implies(X, Y), or(not(X), Y)) 45.25/45.44 = { by axiom 9 (modus_ponens_2) } 45.25/45.44 fresh40(true, true, implies(X, Y), or(not(X), Y)) 45.25/45.44 = { by axiom 8 (modus_ponens_2) } 45.25/45.46 is_a_theorem(or(not(X), Y)) 45.25/45.46 45.25/45.46 Lemma 87: or(X, X) = X. 45.25/45.46 Proof: 45.25/45.46 or(X, X) 45.25/45.46 = { by lemma 65 } 45.25/45.46 fresh3(is_a_theorem(equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by axiom 8 (modus_ponens_2) } 45.25/45.46 fresh3(fresh40(true, true, implies(X, or(X, X)), equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by axiom 9 (modus_ponens_2) } 45.25/45.46 fresh3(fresh40(fresh116(true, true, implies(implies(X, not(not(X))), and(or(not(and(X, X)), X), implies(X, not(not(X)))))), true, implies(X, or(X, X)), equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by axiom 9 (modus_ponens_2) } 45.25/45.46 fresh3(fresh40(fresh116(fresh116(true, true, or(not(and(X, X)), X)), true, implies(implies(X, not(not(X))), and(or(not(and(X, X)), X), implies(X, not(not(X)))))), true, implies(X, or(X, X)), equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by lemma 75 } 45.25/45.46 fresh3(fresh40(fresh116(fresh116(is_a_theorem(implies(and(X, X), X)), true, or(not(and(X, X)), X)), true, implies(implies(X, not(not(X))), and(or(not(and(X, X)), X), implies(X, not(not(X)))))), true, implies(X, or(X, X)), equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by lemma 86 } 45.25/45.46 fresh3(fresh40(fresh116(is_a_theorem(or(not(and(X, X)), X)), true, implies(implies(X, not(not(X))), and(or(not(and(X, X)), X), implies(X, not(not(X)))))), true, implies(X, or(X, X)), equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by lemma 69 } 45.25/45.46 fresh3(fresh40(is_a_theorem(implies(implies(X, not(not(X))), and(or(not(and(X, X)), X), implies(X, not(not(X)))))), true, implies(X, or(X, X)), equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by lemma 80 } 45.25/45.46 fresh3(fresh40(is_a_theorem(implies(implies(X, not(and(not(X), not(X)))), and(or(not(and(X, X)), X), implies(X, not(not(X)))))), true, implies(X, or(X, X)), equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by lemma 64 } 45.25/45.46 fresh3(fresh40(is_a_theorem(implies(implies(X, implies(not(X), X)), and(or(not(and(X, X)), X), implies(X, not(not(X)))))), true, implies(X, or(X, X)), equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by lemma 73 } 45.25/45.46 fresh3(fresh40(is_a_theorem(implies(implies(X, or(X, X)), and(or(not(and(X, X)), X), implies(X, not(not(X)))))), true, implies(X, or(X, X)), equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by lemma 80 } 45.25/45.46 fresh3(fresh40(is_a_theorem(implies(implies(X, or(X, X)), and(or(not(X), X), implies(X, not(not(X)))))), true, implies(X, or(X, X)), equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by lemma 73 } 45.25/45.46 fresh3(fresh40(is_a_theorem(implies(implies(X, or(X, X)), and(implies(not(not(X)), X), implies(X, not(not(X)))))), true, implies(X, or(X, X)), equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by axiom 38 (op_equiv) } 45.25/45.46 fresh3(fresh40(is_a_theorem(implies(implies(X, or(X, X)), fresh30(op_equiv, true, not(not(X)), X))), true, implies(X, or(X, X)), equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by axiom 51 (hilbert_op_equiv) } 45.25/45.46 fresh3(fresh40(is_a_theorem(implies(implies(X, or(X, X)), fresh30(true, true, not(not(X)), X))), true, implies(X, or(X, X)), equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by axiom 14 (op_equiv) } 45.25/45.46 fresh3(fresh40(is_a_theorem(implies(implies(X, or(X, X)), equiv(not(not(X)), X))), true, implies(X, or(X, X)), equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by lemma 80 } 45.25/45.46 fresh3(fresh40(is_a_theorem(implies(implies(X, or(X, X)), equiv(not(and(not(X), not(X))), X))), true, implies(X, or(X, X)), equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by lemma 64 } 45.25/45.46 fresh3(fresh40(is_a_theorem(implies(implies(X, or(X, X)), equiv(implies(not(X), X), X))), true, implies(X, or(X, X)), equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by lemma 73 } 45.25/45.46 fresh3(fresh40(is_a_theorem(implies(implies(X, or(X, X)), equiv(or(X, X), X))), true, implies(X, or(X, X)), equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by lemma 67 } 45.25/45.46 fresh3(fresh116(is_a_theorem(implies(X, or(X, X))), true, equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by axiom 35 (or_1_1) } 45.25/45.46 fresh3(fresh116(fresh21(or_1, true, X, X), true, equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by axiom 46 (hilbert_or_1) } 45.25/45.46 fresh3(fresh116(fresh21(true, true, X, X), true, equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by axiom 19 (or_1_1) } 45.25/45.46 fresh3(fresh116(true, true, equiv(or(X, X), X)), true, or(X, X), X) 45.25/45.46 = { by axiom 9 (modus_ponens_2) } 45.25/45.46 fresh3(true, true, or(X, X), X) 45.25/45.46 = { by axiom 23 (substitution_of_equivalents_2) } 45.25/45.46 X 45.25/45.46 45.25/45.46 Lemma 88: not(not(X)) = X. 45.25/45.46 Proof: 45.25/45.46 not(not(X)) 45.25/45.46 = { by lemma 81 } 45.25/45.46 or(X, X) 45.25/45.46 = { by lemma 87 } 45.39/45.62 X 45.39/45.62 45.39/45.62 Goal 1 (s1_0_axiom_m1): axiom_m1 = true. 45.39/45.62 Proof: 45.39/45.62 axiom_m1 45.39/45.62 = { by axiom 55 (axiom_m1) } 45.39/45.62 fresh92(is_a_theorem(strict_implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by axiom 18 (op_strict_implies) } 45.39/45.62 fresh92(is_a_theorem(fresh23(true, true, and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by axiom 63 (s1_0_op_strict_implies) } 45.39/45.62 fresh92(is_a_theorem(fresh23(op_strict_implies, true, and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by axiom 58 (op_strict_implies) } 45.39/45.62 fresh92(is_a_theorem(necessarily(implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X)))), true) 45.39/45.62 = { by axiom 12 (necessitation_1) } 45.39/45.62 fresh92(fresh34(true, true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by axiom 61 (km5_necessitation) } 45.39/45.62 fresh92(fresh34(necessitation, true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by axiom 56 (necessitation_1) } 45.39/45.62 fresh92(fresh33(is_a_theorem(implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 87 } 45.39/45.62 fresh92(fresh33(is_a_theorem(implies(and(sK28_axiom_m1_X, or(sK27_axiom_m1_Y, sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 73 } 45.39/45.62 fresh92(fresh33(is_a_theorem(implies(and(sK28_axiom_m1_X, implies(not(sK27_axiom_m1_Y), sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 64 } 45.39/45.62 fresh92(fresh33(is_a_theorem(implies(and(sK28_axiom_m1_X, not(and(not(sK27_axiom_m1_Y), not(sK27_axiom_m1_Y)))), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 80 } 45.39/45.62 fresh92(fresh33(is_a_theorem(implies(and(sK28_axiom_m1_X, not(not(sK27_axiom_m1_Y))), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 88 } 45.39/45.62 fresh92(fresh33(is_a_theorem(implies(not(not(and(sK28_axiom_m1_X, not(not(sK27_axiom_m1_Y))))), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 83 } 45.39/45.62 fresh92(fresh33(is_a_theorem(implies(not(and(implies(?, ?), not(and(sK28_axiom_m1_X, not(not(sK27_axiom_m1_Y)))))), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 64 } 45.39/45.62 fresh92(fresh33(is_a_theorem(implies(implies(implies(?, ?), and(sK28_axiom_m1_X, not(not(sK27_axiom_m1_Y)))), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 84 } 45.39/45.62 fresh92(fresh33(is_a_theorem(or(and(implies(?, ?), not(and(sK28_axiom_m1_X, not(not(sK27_axiom_m1_Y))))), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 64 } 45.39/45.62 fresh92(fresh33(is_a_theorem(or(and(implies(?, ?), implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y))), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 83 } 45.39/45.62 fresh92(fresh33(is_a_theorem(or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by axiom 8 (modus_ponens_2) } 45.39/45.62 fresh92(fresh33(fresh40(true, true, or(and(sK27_axiom_m1_Y, sK28_axiom_m1_X), not(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y))))), or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by axiom 11 (modus_tollens_1) } 45.39/45.62 fresh92(fresh33(fresh40(fresh35(true, true, not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y))), and(sK27_axiom_m1_Y, sK28_axiom_m1_X)), true, or(and(sK27_axiom_m1_Y, sK28_axiom_m1_X), not(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y))))), or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by axiom 40 (hilbert_modus_tollens) } 45.39/45.62 fresh92(fresh33(fresh40(fresh35(modus_tollens, true, not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y))), and(sK27_axiom_m1_Y, sK28_axiom_m1_X)), true, or(and(sK27_axiom_m1_Y, sK28_axiom_m1_X), not(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y))))), or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by axiom 33 (modus_tollens_1) } 45.39/45.62 fresh92(fresh33(fresh40(is_a_theorem(implies(implies(not(and(sK27_axiom_m1_Y, sK28_axiom_m1_X)), not(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y))))), implies(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y))), and(sK27_axiom_m1_Y, sK28_axiom_m1_X)))), true, or(and(sK27_axiom_m1_Y, sK28_axiom_m1_X), not(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y))))), or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 73 } 45.39/45.62 fresh92(fresh33(fresh40(is_a_theorem(implies(or(and(sK27_axiom_m1_Y, sK28_axiom_m1_X), not(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y))))), implies(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y))), and(sK27_axiom_m1_Y, sK28_axiom_m1_X)))), true, or(and(sK27_axiom_m1_Y, sK28_axiom_m1_X), not(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y))))), or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 73 } 45.39/45.62 fresh92(fresh33(fresh40(is_a_theorem(implies(or(and(sK27_axiom_m1_Y, sK28_axiom_m1_X), not(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y))))), or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X)))), true, or(and(sK27_axiom_m1_Y, sK28_axiom_m1_X), not(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y))))), or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 67 } 45.39/45.62 fresh92(fresh33(fresh116(is_a_theorem(or(and(sK27_axiom_m1_Y, sK28_axiom_m1_X), not(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)))))), true, or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 88 } 45.39/45.62 fresh92(fresh33(fresh116(is_a_theorem(or(and(sK27_axiom_m1_Y, not(not(sK28_axiom_m1_X))), not(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)))))), true, or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 87 } 45.39/45.62 fresh92(fresh33(fresh116(is_a_theorem(or(or(and(sK27_axiom_m1_Y, not(not(sK28_axiom_m1_X))), and(sK27_axiom_m1_Y, not(not(sK28_axiom_m1_X)))), not(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)))))), true, or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 84 } 45.39/45.62 fresh92(fresh33(fresh116(is_a_theorem(or(implies(implies(sK27_axiom_m1_Y, not(sK28_axiom_m1_X)), and(sK27_axiom_m1_Y, not(not(sK28_axiom_m1_X)))), not(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)))))), true, or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 64 } 45.39/45.62 fresh92(fresh33(fresh116(is_a_theorem(or(not(and(implies(sK27_axiom_m1_Y, not(sK28_axiom_m1_X)), not(and(sK27_axiom_m1_Y, not(not(sK28_axiom_m1_X)))))), not(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)))))), true, or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 64 } 45.39/45.62 fresh92(fresh33(fresh116(is_a_theorem(or(not(and(implies(sK27_axiom_m1_Y, not(sK28_axiom_m1_X)), implies(sK27_axiom_m1_Y, not(sK28_axiom_m1_X)))), not(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)))))), true, or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 80 } 45.39/45.62 fresh92(fresh33(fresh116(is_a_theorem(or(not(implies(sK27_axiom_m1_Y, not(sK28_axiom_m1_X))), not(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)))))), true, or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 87 } 45.39/45.62 fresh92(fresh33(fresh116(is_a_theorem(or(not(implies(or(sK27_axiom_m1_Y, sK27_axiom_m1_Y), not(sK28_axiom_m1_X))), not(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)))))), true, or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 85 } 45.39/45.62 fresh92(fresh33(fresh116(is_a_theorem(or(not(or(not(sK27_axiom_m1_Y), not(sK28_axiom_m1_X))), not(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)))))), true, or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 80 } 45.39/45.62 fresh92(fresh33(fresh116(is_a_theorem(or(not(or(not(sK27_axiom_m1_Y), not(sK28_axiom_m1_X))), not(and(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y))), not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y))))))), true, or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 64 } 45.39/45.62 fresh92(fresh33(fresh116(is_a_theorem(or(not(or(not(sK27_axiom_m1_Y), not(sK28_axiom_m1_X))), implies(not(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y))), implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y))))), true, or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 73 } 45.39/45.62 fresh92(fresh33(fresh116(is_a_theorem(or(not(or(not(sK27_axiom_m1_Y), not(sK28_axiom_m1_X))), or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y))))), true, or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 87 } 45.39/45.62 fresh92(fresh33(fresh116(is_a_theorem(or(not(or(not(sK27_axiom_m1_Y), not(sK28_axiom_m1_X))), implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)))), true, or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 86 } 45.39/45.62 fresh92(fresh33(fresh116(fresh116(is_a_theorem(implies(or(not(sK27_axiom_m1_Y), not(sK28_axiom_m1_X)), implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)))), true, or(not(or(not(sK27_axiom_m1_Y), not(sK28_axiom_m1_X))), implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)))), true, or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by lemma 73 } 45.39/45.62 fresh92(fresh33(fresh116(fresh116(is_a_theorem(implies(implies(not(not(sK27_axiom_m1_Y)), not(sK28_axiom_m1_X)), implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)))), true, or(not(or(not(sK27_axiom_m1_Y), not(sK28_axiom_m1_X))), implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)))), true, or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by axiom 33 (modus_tollens_1) } 45.39/45.62 fresh92(fresh33(fresh116(fresh116(fresh35(modus_tollens, true, sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), true, or(not(or(not(sK27_axiom_m1_Y), not(sK28_axiom_m1_X))), implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)))), true, or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by axiom 40 (hilbert_modus_tollens) } 45.39/45.62 fresh92(fresh33(fresh116(fresh116(fresh35(true, true, sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), true, or(not(or(not(sK27_axiom_m1_Y), not(sK28_axiom_m1_X))), implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)))), true, or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by axiom 11 (modus_tollens_1) } 45.39/45.62 fresh92(fresh33(fresh116(fresh116(true, true, or(not(or(not(sK27_axiom_m1_Y), not(sK28_axiom_m1_X))), implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)))), true, or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by axiom 9 (modus_ponens_2) } 45.39/45.62 fresh92(fresh33(fresh116(true, true, or(implies(sK28_axiom_m1_X, not(sK27_axiom_m1_Y)), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by axiom 9 (modus_ponens_2) } 45.39/45.62 fresh92(fresh33(true, true, implies(and(sK28_axiom_m1_X, sK27_axiom_m1_Y), and(sK27_axiom_m1_Y, sK28_axiom_m1_X))), true) 45.39/45.62 = { by axiom 13 (necessitation_1) } 45.39/45.62 fresh92(true, true) 45.39/45.62 = { by axiom 5 (axiom_m1) } 45.39/45.62 true 45.39/45.62 % SZS output end Proof 45.39/45.62 45.39/45.62 RESULT: Theorem (the conjecture is true). 45.46/45.64 EOF