TSTP Solution File: LCL535+1 by Twee---2.4.2

View Problem - Process Solution

%------------------------------------------------------------------------------
% File     : Twee---2.4.2
% Problem  : LCL535+1 : TPTP v8.1.2. Released v3.3.0.
% Transfm  : none
% Format   : tptp:raw
% Command  : parallel-twee %s --tstp --conditional-encoding if --smaller --drop-non-horn --give-up-on-saturation --explain-encoding --formal-proof

% Computer : n018.cluster.edu
% Model    : x86_64 x86_64
% CPU      : Intel(R) Xeon(R) CPU E5-2620 v4 2.10GHz
% Memory   : 8042.1875MB
% OS       : Linux 3.10.0-693.el7.x86_64
% CPULimit : 300s
% WCLimit  : 300s
% DateTime : Thu Aug 31 08:19:20 EDT 2023

% Result   : Theorem 20.69s 3.02s
% Output   : Proof 20.69s
% Verified : 
% SZS Type : -

% Comments : 
%------------------------------------------------------------------------------
%----WARNING: Could not form TPTP format derivation
%------------------------------------------------------------------------------
%----ORIGINAL SYSTEM OUTPUT
% 0.00/0.12  % Problem  : LCL535+1 : TPTP v8.1.2. Released v3.3.0.
% 0.00/0.13  % Command  : parallel-twee %s --tstp --conditional-encoding if --smaller --drop-non-horn --give-up-on-saturation --explain-encoding --formal-proof
% 0.13/0.35  % Computer : n018.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 : 300
% 0.13/0.35  % WCLimit  : 300
% 0.13/0.35  % DateTime : Fri Aug 25 05:59:13 EDT 2023
% 0.13/0.35  % CPUTime  : 
% 20.69/3.02  Command-line arguments: --lhs-weight 1 --flip-ordering --normalise-queue-percent 10 --cp-renormalise-threshold 10
% 20.69/3.02  
% 20.69/3.02  % SZS status Theorem
% 20.69/3.02  
% 20.69/3.04  % SZS output start Proof
% 20.69/3.04  Take the following subset of the input axioms:
% 20.69/3.04    fof(and_1, axiom, and_1 <=> ![X, Y]: is_a_theorem(implies(and(X, Y), X))).
% 20.69/3.04    fof(and_3, axiom, and_3 <=> ![X2, Y2]: is_a_theorem(implies(X2, implies(Y2, and(X2, Y2))))).
% 20.69/3.04    fof(axiom_5, axiom, axiom_5 <=> ![X2]: is_a_theorem(implies(possibly(X2), necessarily(possibly(X2))))).
% 20.69/3.04    fof(axiom_M, axiom, axiom_M <=> ![X2]: is_a_theorem(implies(necessarily(X2), X2))).
% 20.69/3.04    fof(axiom_m9, axiom, axiom_m9 <=> ![X2]: is_a_theorem(strict_implies(possibly(possibly(X2)), possibly(X2)))).
% 20.69/3.04    fof(cn3, axiom, cn3 <=> ![P]: is_a_theorem(implies(implies(not(P), P), P))).
% 20.69/3.04    fof(equivalence_3, axiom, equivalence_3 <=> ![X2, Y2]: is_a_theorem(implies(implies(X2, Y2), implies(implies(Y2, X2), equiv(X2, Y2))))).
% 20.69/3.04    fof(hilbert_and_1, axiom, and_1).
% 20.69/3.04    fof(hilbert_and_3, axiom, and_3).
% 20.69/3.04    fof(hilbert_equivalence_3, axiom, equivalence_3).
% 20.69/3.04    fof(hilbert_implies_1, axiom, implies_1).
% 20.69/3.04    fof(hilbert_implies_2, axiom, implies_2).
% 20.69/3.04    fof(hilbert_modus_ponens, axiom, modus_ponens).
% 20.69/3.04    fof(hilbert_op_implies_and, axiom, op_implies_and).
% 20.69/3.04    fof(hilbert_op_or, axiom, op_or).
% 20.69/3.04    fof(hilbert_or_3, axiom, or_3).
% 20.69/3.04    fof(implies_1, axiom, implies_1 <=> ![X2, Y2]: is_a_theorem(implies(X2, implies(Y2, X2)))).
% 20.69/3.04    fof(implies_2, axiom, implies_2 <=> ![X2, Y2]: is_a_theorem(implies(implies(X2, implies(X2, Y2)), implies(X2, Y2)))).
% 20.69/3.04    fof(km5_axiom_5, axiom, axiom_5).
% 20.69/3.04    fof(km5_axiom_M, axiom, axiom_M).
% 20.69/3.04    fof(km5_necessitation, axiom, necessitation).
% 20.69/3.04    fof(km5_op_possibly, axiom, op_possibly).
% 20.69/3.05    fof(modus_ponens, axiom, modus_ponens <=> ![X2, Y2]: ((is_a_theorem(X2) & is_a_theorem(implies(X2, Y2))) => is_a_theorem(Y2))).
% 20.69/3.05    fof(necessitation, axiom, necessitation <=> ![X2]: (is_a_theorem(X2) => is_a_theorem(necessarily(X2)))).
% 20.69/3.05    fof(op_implies_and, axiom, op_implies_and => ![X2, Y2]: implies(X2, Y2)=not(and(X2, not(Y2)))).
% 20.69/3.05    fof(op_or, axiom, op_or => ![X2, Y2]: or(X2, Y2)=not(and(not(X2), not(Y2)))).
% 20.69/3.05    fof(op_possibly, axiom, op_possibly => ![X2]: possibly(X2)=not(necessarily(not(X2)))).
% 20.69/3.05    fof(op_strict_implies, axiom, op_strict_implies => ![X2, Y2]: strict_implies(X2, Y2)=necessarily(implies(X2, Y2))).
% 20.69/3.05    fof(or_3, axiom, or_3 <=> ![Z, X2, Y2]: is_a_theorem(implies(implies(X2, Z), implies(implies(Y2, Z), implies(or(X2, Y2), Z))))).
% 20.69/3.05    fof(s1_0_m6s3m9b_axiom_m9, conjecture, axiom_m9).
% 20.69/3.05    fof(s1_0_op_strict_implies, axiom, op_strict_implies).
% 20.69/3.05    fof(substitution_of_equivalents, axiom, substitution_of_equivalents <=> ![X2, Y2]: (is_a_theorem(equiv(X2, Y2)) => X2=Y2)).
% 20.69/3.05    fof(substitution_of_equivalents, axiom, substitution_of_equivalents).
% 20.69/3.05  
% 20.69/3.05  Now clausify the problem and encode Horn clauses using encoding 3 of
% 20.69/3.05  http://www.cse.chalmers.se/~nicsma/papers/horn.pdf.
% 20.69/3.05  We repeatedly replace C & s=t => u=v by the two clauses:
% 20.69/3.05    fresh(y, y, x1...xn) = u
% 20.69/3.05    C => fresh(s, t, x1...xn) = v
% 20.69/3.05  where fresh is a fresh function symbol and x1..xn are the free
% 20.69/3.05  variables of u and v.
% 20.69/3.05  A predicate p(X) is encoded as p(X)=true (this is sound, because the
% 20.69/3.05  input problem has no model of domain size 1).
% 20.69/3.05  
% 20.69/3.05  The encoding turns the above axioms into the following unit equations and goals:
% 20.69/3.05  
% 20.69/3.05  Axiom 1 (hilbert_modus_ponens): modus_ponens = true.
% 20.69/3.05  Axiom 2 (substitution_of_equivalents): substitution_of_equivalents = true.
% 20.69/3.05  Axiom 3 (hilbert_implies_1): implies_1 = true.
% 20.69/3.05  Axiom 4 (hilbert_implies_2): implies_2 = true.
% 20.69/3.05  Axiom 5 (hilbert_and_1): and_1 = true.
% 20.69/3.05  Axiom 6 (hilbert_and_3): and_3 = true.
% 20.69/3.05  Axiom 7 (hilbert_or_3): or_3 = true.
% 20.69/3.05  Axiom 8 (hilbert_equivalence_3): equivalence_3 = true.
% 20.69/3.05  Axiom 9 (hilbert_op_or): op_or = true.
% 20.69/3.05  Axiom 10 (km5_necessitation): necessitation = true.
% 20.69/3.05  Axiom 11 (km5_axiom_M): axiom_M = true.
% 20.69/3.05  Axiom 12 (km5_axiom_5): axiom_5 = true.
% 20.69/3.05  Axiom 13 (km5_op_possibly): op_possibly = true.
% 20.69/3.05  Axiom 14 (hilbert_op_implies_and): op_implies_and = true.
% 20.69/3.05  Axiom 15 (s1_0_op_strict_implies): op_strict_implies = true.
% 20.69/3.05  Axiom 16 (axiom_m9): fresh74(X, X) = true.
% 20.69/3.05  Axiom 17 (modus_ponens_2): fresh116(X, X, Y) = true.
% 20.69/3.05  Axiom 18 (axiom_5_1): fresh99(X, X, Y) = true.
% 20.69/3.05  Axiom 19 (axiom_M_1): fresh93(X, X, Y) = true.
% 20.69/3.05  Axiom 20 (modus_ponens_2): fresh40(X, X, Y) = is_a_theorem(Y).
% 20.69/3.05  Axiom 21 (necessitation_1): fresh34(X, X, Y) = is_a_theorem(necessarily(Y)).
% 20.69/3.05  Axiom 22 (necessitation_1): fresh33(X, X, Y) = true.
% 20.69/3.05  Axiom 23 (op_possibly): fresh25(X, X, Y) = possibly(Y).
% 20.69/3.05  Axiom 24 (op_possibly): fresh25(op_possibly, true, X) = not(necessarily(not(X))).
% 20.69/3.05  Axiom 25 (axiom_M_1): fresh93(axiom_M, true, X) = is_a_theorem(implies(necessarily(X), X)).
% 20.69/3.05  Axiom 26 (modus_ponens_2): fresh115(X, X, Y, Z) = fresh116(modus_ponens, true, Z).
% 20.69/3.05  Axiom 27 (and_1_1): fresh107(X, X, Y, Z) = true.
% 20.69/3.05  Axiom 28 (and_3_1): fresh103(X, X, Y, Z) = true.
% 20.69/3.05  Axiom 29 (equivalence_3_1): fresh53(X, X, Y, Z) = true.
% 20.69/3.05  Axiom 30 (implies_1_1): fresh51(X, X, Y, Z) = true.
% 20.69/3.05  Axiom 31 (implies_2_1): fresh49(X, X, Y, Z) = true.
% 20.69/3.05  Axiom 32 (necessitation_1): fresh34(necessitation, true, X) = fresh33(is_a_theorem(X), true, X).
% 20.69/3.05  Axiom 33 (op_implies_and): fresh29(X, X, Y, Z) = implies(Y, Z).
% 20.69/3.05  Axiom 34 (op_implies_and): fresh29(op_implies_and, true, X, Y) = not(and(X, not(Y))).
% 20.69/3.05  Axiom 35 (op_or): fresh26(X, X, Y, Z) = or(Y, Z).
% 20.69/3.05  Axiom 36 (op_strict_implies): fresh23(X, X, Y, Z) = strict_implies(Y, Z).
% 20.69/3.05  Axiom 37 (op_strict_implies): fresh23(op_strict_implies, true, X, Y) = necessarily(implies(X, Y)).
% 20.69/3.05  Axiom 38 (substitution_of_equivalents_2): fresh4(X, X, Y, Z) = Y.
% 20.69/3.05  Axiom 39 (substitution_of_equivalents_2): fresh3(X, X, Y, Z) = Z.
% 20.69/3.05  Axiom 40 (implies_1_1): fresh51(implies_1, true, X, Y) = is_a_theorem(implies(X, implies(Y, X))).
% 20.69/3.05  Axiom 41 (and_1_1): fresh107(and_1, true, X, Y) = is_a_theorem(implies(and(X, Y), X)).
% 20.69/3.05  Axiom 42 (op_or): fresh26(op_or, true, X, Y) = not(and(not(X), not(Y))).
% 20.69/3.05  Axiom 43 (or_3_1): fresh17(X, X, Y, Z, W) = true.
% 20.69/3.05  Axiom 44 (axiom_5_1): fresh99(axiom_5, true, X) = is_a_theorem(implies(possibly(X), necessarily(possibly(X)))).
% 20.69/3.05  Axiom 45 (cn3_1): fresh59(cn3, true, X) = is_a_theorem(implies(implies(not(X), X), X)).
% 20.69/3.05  Axiom 46 (and_3_1): fresh103(and_3, true, X, Y) = is_a_theorem(implies(X, implies(Y, and(X, Y)))).
% 20.69/3.05  Axiom 47 (modus_ponens_2): fresh115(is_a_theorem(implies(X, Y)), true, X, Y) = fresh40(is_a_theorem(X), true, Y).
% 20.69/3.05  Axiom 48 (substitution_of_equivalents_2): fresh4(substitution_of_equivalents, true, X, Y) = fresh3(is_a_theorem(equiv(X, Y)), true, X, Y).
% 20.69/3.05  Axiom 49 (axiom_m9): fresh74(is_a_theorem(strict_implies(possibly(possibly(x2)), possibly(x2))), true) = axiom_m9.
% 20.69/3.05  Axiom 50 (implies_2_1): fresh49(implies_2, true, X, Y) = is_a_theorem(implies(implies(X, implies(X, Y)), implies(X, Y))).
% 20.69/3.05  Axiom 51 (equivalence_3_1): fresh53(equivalence_3, true, X, Y) = is_a_theorem(implies(implies(X, Y), implies(implies(Y, X), equiv(X, Y)))).
% 20.69/3.05  Axiom 52 (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)))).
% 20.69/3.05  
% 20.69/3.05  Lemma 53: fresh115(X, X, Y, Z) = true.
% 20.69/3.05  Proof:
% 20.69/3.05    fresh115(X, X, Y, Z)
% 20.69/3.05  = { by axiom 26 (modus_ponens_2) }
% 20.69/3.05    fresh116(modus_ponens, true, Z)
% 20.69/3.05  = { by axiom 1 (hilbert_modus_ponens) }
% 20.69/3.05    fresh116(true, true, Z)
% 20.69/3.05  = { by axiom 17 (modus_ponens_2) }
% 20.69/3.05    true
% 20.69/3.05  
% 20.69/3.05  Lemma 54: fresh40(is_a_theorem(implies(X, Y)), true, implies(implies(Y, X), equiv(X, Y))) = true.
% 20.69/3.05  Proof:
% 20.69/3.05    fresh40(is_a_theorem(implies(X, Y)), true, implies(implies(Y, X), equiv(X, Y)))
% 20.69/3.05  = { by axiom 47 (modus_ponens_2) R->L }
% 20.69/3.05    fresh115(is_a_theorem(implies(implies(X, Y), implies(implies(Y, X), equiv(X, Y)))), true, implies(X, Y), implies(implies(Y, X), equiv(X, Y)))
% 20.69/3.05  = { by axiom 51 (equivalence_3_1) R->L }
% 20.69/3.05    fresh115(fresh53(equivalence_3, true, X, Y), true, implies(X, Y), implies(implies(Y, X), equiv(X, Y)))
% 20.69/3.05  = { by axiom 8 (hilbert_equivalence_3) }
% 20.69/3.05    fresh115(fresh53(true, true, X, Y), true, implies(X, Y), implies(implies(Y, X), equiv(X, Y)))
% 20.69/3.05  = { by axiom 29 (equivalence_3_1) }
% 20.69/3.05    fresh115(true, true, implies(X, Y), implies(implies(Y, X), equiv(X, Y)))
% 20.69/3.05  = { by lemma 53 }
% 20.69/3.05    true
% 20.69/3.05  
% 20.69/3.05  Lemma 55: fresh3(is_a_theorem(equiv(X, Y)), true, X, Y) = X.
% 20.69/3.05  Proof:
% 20.69/3.05    fresh3(is_a_theorem(equiv(X, Y)), true, X, Y)
% 20.69/3.05  = { by axiom 48 (substitution_of_equivalents_2) R->L }
% 20.69/3.05    fresh4(substitution_of_equivalents, true, X, Y)
% 20.69/3.05  = { by axiom 2 (substitution_of_equivalents) }
% 20.69/3.05    fresh4(true, true, X, Y)
% 20.69/3.05  = { by axiom 38 (substitution_of_equivalents_2) }
% 20.69/3.05    X
% 20.69/3.05  
% 20.69/3.05  Lemma 56: necessarily(possibly(X)) = possibly(X).
% 20.69/3.05  Proof:
% 20.69/3.05    necessarily(possibly(X))
% 20.69/3.05  = { by axiom 39 (substitution_of_equivalents_2) R->L }
% 20.69/3.05    fresh3(true, true, possibly(X), necessarily(possibly(X)))
% 20.69/3.05  = { by lemma 53 R->L }
% 20.69/3.05    fresh3(fresh115(true, true, implies(necessarily(possibly(X)), possibly(X)), equiv(possibly(X), necessarily(possibly(X)))), true, possibly(X), necessarily(possibly(X)))
% 20.69/3.05  = { by lemma 54 R->L }
% 20.69/3.05    fresh3(fresh115(fresh40(is_a_theorem(implies(possibly(X), necessarily(possibly(X)))), true, implies(implies(necessarily(possibly(X)), possibly(X)), equiv(possibly(X), necessarily(possibly(X))))), true, implies(necessarily(possibly(X)), possibly(X)), equiv(possibly(X), necessarily(possibly(X)))), true, possibly(X), necessarily(possibly(X)))
% 20.69/3.05  = { by axiom 44 (axiom_5_1) R->L }
% 20.69/3.05    fresh3(fresh115(fresh40(fresh99(axiom_5, true, X), true, implies(implies(necessarily(possibly(X)), possibly(X)), equiv(possibly(X), necessarily(possibly(X))))), true, implies(necessarily(possibly(X)), possibly(X)), equiv(possibly(X), necessarily(possibly(X)))), true, possibly(X), necessarily(possibly(X)))
% 20.69/3.05  = { by axiom 12 (km5_axiom_5) }
% 20.69/3.05    fresh3(fresh115(fresh40(fresh99(true, true, X), true, implies(implies(necessarily(possibly(X)), possibly(X)), equiv(possibly(X), necessarily(possibly(X))))), true, implies(necessarily(possibly(X)), possibly(X)), equiv(possibly(X), necessarily(possibly(X)))), true, possibly(X), necessarily(possibly(X)))
% 20.69/3.05  = { by axiom 18 (axiom_5_1) }
% 20.69/3.05    fresh3(fresh115(fresh40(true, true, implies(implies(necessarily(possibly(X)), possibly(X)), equiv(possibly(X), necessarily(possibly(X))))), true, implies(necessarily(possibly(X)), possibly(X)), equiv(possibly(X), necessarily(possibly(X)))), true, possibly(X), necessarily(possibly(X)))
% 20.69/3.05  = { by axiom 20 (modus_ponens_2) }
% 20.69/3.05    fresh3(fresh115(is_a_theorem(implies(implies(necessarily(possibly(X)), possibly(X)), equiv(possibly(X), necessarily(possibly(X))))), true, implies(necessarily(possibly(X)), possibly(X)), equiv(possibly(X), necessarily(possibly(X)))), true, possibly(X), necessarily(possibly(X)))
% 20.69/3.05  = { by axiom 47 (modus_ponens_2) }
% 20.69/3.05    fresh3(fresh40(is_a_theorem(implies(necessarily(possibly(X)), possibly(X))), true, equiv(possibly(X), necessarily(possibly(X)))), true, possibly(X), necessarily(possibly(X)))
% 20.69/3.05  = { by axiom 25 (axiom_M_1) R->L }
% 20.69/3.05    fresh3(fresh40(fresh93(axiom_M, true, possibly(X)), true, equiv(possibly(X), necessarily(possibly(X)))), true, possibly(X), necessarily(possibly(X)))
% 20.69/3.05  = { by axiom 11 (km5_axiom_M) }
% 20.69/3.05    fresh3(fresh40(fresh93(true, true, possibly(X)), true, equiv(possibly(X), necessarily(possibly(X)))), true, possibly(X), necessarily(possibly(X)))
% 20.69/3.05  = { by axiom 19 (axiom_M_1) }
% 20.69/3.05    fresh3(fresh40(true, true, equiv(possibly(X), necessarily(possibly(X)))), true, possibly(X), necessarily(possibly(X)))
% 20.69/3.05  = { by axiom 20 (modus_ponens_2) }
% 20.69/3.05    fresh3(is_a_theorem(equiv(possibly(X), necessarily(possibly(X)))), true, possibly(X), necessarily(possibly(X)))
% 20.69/3.05  = { by lemma 55 }
% 20.69/3.05    possibly(X)
% 20.69/3.05  
% 20.69/3.05  Lemma 57: not(and(X, not(Y))) = implies(X, Y).
% 20.69/3.05  Proof:
% 20.69/3.05    not(and(X, not(Y)))
% 20.69/3.05  = { by axiom 34 (op_implies_and) R->L }
% 20.69/3.05    fresh29(op_implies_and, true, X, Y)
% 20.69/3.05  = { by axiom 14 (hilbert_op_implies_and) }
% 20.69/3.05    fresh29(true, true, X, Y)
% 20.69/3.05  = { by axiom 33 (op_implies_and) }
% 20.69/3.05    implies(X, Y)
% 20.69/3.05  
% 20.69/3.05  Lemma 58: implies(not(X), Y) = or(X, Y).
% 20.69/3.05  Proof:
% 20.69/3.05    implies(not(X), Y)
% 20.69/3.05  = { by lemma 57 R->L }
% 20.69/3.05    not(and(not(X), not(Y)))
% 20.69/3.05  = { by axiom 42 (op_or) R->L }
% 20.69/3.05    fresh26(op_or, true, X, Y)
% 20.69/3.05  = { by axiom 9 (hilbert_op_or) }
% 20.69/3.05    fresh26(true, true, X, Y)
% 20.69/3.05  = { by axiom 35 (op_or) }
% 20.69/3.05    or(X, Y)
% 20.69/3.05  
% 20.69/3.05  Lemma 59: not(necessarily(not(X))) = possibly(X).
% 20.69/3.05  Proof:
% 20.69/3.05    not(necessarily(not(X)))
% 20.69/3.05  = { by axiom 24 (op_possibly) R->L }
% 20.69/3.05    fresh25(op_possibly, true, X)
% 20.69/3.05  = { by axiom 13 (km5_op_possibly) }
% 20.69/3.05    fresh25(true, true, X)
% 20.69/3.05  = { by axiom 23 (op_possibly) }
% 20.69/3.05    possibly(X)
% 20.69/3.05  
% 20.69/3.05  Lemma 60: or(necessarily(not(X)), Y) = implies(possibly(X), Y).
% 20.69/3.05  Proof:
% 20.69/3.05    or(necessarily(not(X)), Y)
% 20.69/3.05  = { by lemma 58 R->L }
% 20.69/3.05    implies(not(necessarily(not(X))), Y)
% 20.69/3.05  = { by lemma 59 }
% 20.69/3.05    implies(possibly(X), Y)
% 20.69/3.05  
% 20.69/3.05  Lemma 61: is_a_theorem(implies(or(X, X), X)) = fresh59(cn3, true, X).
% 20.69/3.05  Proof:
% 20.69/3.05    is_a_theorem(implies(or(X, X), X))
% 20.69/3.05  = { by lemma 58 R->L }
% 20.69/3.05    is_a_theorem(implies(implies(not(X), X), X))
% 20.69/3.05  = { by axiom 45 (cn3_1) R->L }
% 20.69/3.05    fresh59(cn3, true, X)
% 20.69/3.05  
% 20.69/3.05  Lemma 62: fresh40(is_a_theorem(implies(X, implies(X, Y))), true, implies(X, Y)) = true.
% 20.69/3.05  Proof:
% 20.69/3.05    fresh40(is_a_theorem(implies(X, implies(X, Y))), true, implies(X, Y))
% 20.69/3.05  = { by axiom 47 (modus_ponens_2) R->L }
% 20.69/3.05    fresh115(is_a_theorem(implies(implies(X, implies(X, Y)), implies(X, Y))), true, implies(X, implies(X, Y)), implies(X, Y))
% 20.69/3.05  = { by axiom 50 (implies_2_1) R->L }
% 20.69/3.05    fresh115(fresh49(implies_2, true, X, Y), true, implies(X, implies(X, Y)), implies(X, Y))
% 20.69/3.05  = { by axiom 4 (hilbert_implies_2) }
% 20.69/3.05    fresh115(fresh49(true, true, X, Y), true, implies(X, implies(X, Y)), implies(X, Y))
% 20.69/3.05  = { by axiom 31 (implies_2_1) }
% 20.69/3.05    fresh115(true, true, implies(X, implies(X, Y)), implies(X, Y))
% 20.69/3.05  = { by lemma 53 }
% 20.69/3.06    true
% 20.69/3.06  
% 20.69/3.06  Goal 1 (s1_0_m6s3m9b_axiom_m9): axiom_m9 = true.
% 20.69/3.06  Proof:
% 20.69/3.06    axiom_m9
% 20.69/3.06  = { by axiom 49 (axiom_m9) R->L }
% 20.69/3.06    fresh74(is_a_theorem(strict_implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by axiom 36 (op_strict_implies) R->L }
% 20.69/3.06    fresh74(is_a_theorem(fresh23(true, true, possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by axiom 15 (s1_0_op_strict_implies) R->L }
% 20.69/3.06    fresh74(is_a_theorem(fresh23(op_strict_implies, true, possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by axiom 37 (op_strict_implies) }
% 20.69/3.06    fresh74(is_a_theorem(necessarily(implies(possibly(possibly(x2)), possibly(x2)))), true)
% 20.69/3.06  = { by axiom 21 (necessitation_1) R->L }
% 20.69/3.06    fresh74(fresh34(true, true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by axiom 10 (km5_necessitation) R->L }
% 20.69/3.06    fresh74(fresh34(necessitation, true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by axiom 32 (necessitation_1) }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(implies(possibly(possibly(x2)), possibly(x2))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by lemma 56 R->L }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(implies(possibly(possibly(x2)), necessarily(possibly(x2)))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by lemma 56 R->L }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(implies(possibly(necessarily(possibly(x2))), necessarily(possibly(x2)))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by lemma 60 R->L }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(or(necessarily(not(necessarily(possibly(x2)))), necessarily(possibly(x2)))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by lemma 59 R->L }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(or(necessarily(not(necessarily(not(necessarily(not(x2)))))), necessarily(possibly(x2)))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by lemma 59 }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(or(necessarily(possibly(necessarily(not(x2)))), necessarily(possibly(x2)))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by lemma 56 }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(or(possibly(necessarily(not(x2))), necessarily(possibly(x2)))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by lemma 59 R->L }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(or(possibly(necessarily(not(x2))), necessarily(not(necessarily(not(x2)))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by lemma 55 R->L }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(or(fresh3(is_a_theorem(equiv(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))))), true, possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))), necessarily(not(necessarily(not(x2)))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by axiom 20 (modus_ponens_2) R->L }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(or(fresh3(fresh40(true, true, equiv(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))))), true, possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))), necessarily(not(necessarily(not(x2)))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by axiom 27 (and_1_1) R->L }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(or(fresh3(fresh40(fresh107(true, true, possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), true, equiv(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))))), true, possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))), necessarily(not(necessarily(not(x2)))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by axiom 5 (hilbert_and_1) R->L }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(or(fresh3(fresh40(fresh107(and_1, true, possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), true, equiv(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))))), true, possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))), necessarily(not(necessarily(not(x2)))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by axiom 41 (and_1_1) }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(or(fresh3(fresh40(is_a_theorem(implies(and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), possibly(necessarily(not(x2))))), true, equiv(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))))), true, possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))), necessarily(not(necessarily(not(x2)))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by axiom 47 (modus_ponens_2) R->L }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(or(fresh3(fresh115(is_a_theorem(implies(implies(and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), possibly(necessarily(not(x2)))), equiv(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))))), true, implies(and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), possibly(necessarily(not(x2)))), equiv(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))))), true, possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))), necessarily(not(necessarily(not(x2)))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by axiom 20 (modus_ponens_2) R->L }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(or(fresh3(fresh115(fresh40(true, true, implies(implies(and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), possibly(necessarily(not(x2)))), equiv(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))))), true, implies(and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), possibly(necessarily(not(x2)))), equiv(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))))), true, possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))), necessarily(not(necessarily(not(x2)))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by lemma 62 R->L }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(or(fresh3(fresh115(fresh40(fresh40(is_a_theorem(implies(possibly(necessarily(not(x2))), implies(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))))), true, implies(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))))), true, implies(implies(and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), possibly(necessarily(not(x2)))), equiv(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))))), true, implies(and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), possibly(necessarily(not(x2)))), equiv(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))))), true, possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))), necessarily(not(necessarily(not(x2)))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by axiom 46 (and_3_1) R->L }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(or(fresh3(fresh115(fresh40(fresh40(fresh103(and_3, true, possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), true, implies(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))))), true, implies(implies(and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), possibly(necessarily(not(x2)))), equiv(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))))), true, implies(and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), possibly(necessarily(not(x2)))), equiv(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))))), true, possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))), necessarily(not(necessarily(not(x2)))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by axiom 6 (hilbert_and_3) }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(or(fresh3(fresh115(fresh40(fresh40(fresh103(true, true, possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), true, implies(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))))), true, implies(implies(and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), possibly(necessarily(not(x2)))), equiv(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))))), true, implies(and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), possibly(necessarily(not(x2)))), equiv(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))))), true, possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))), necessarily(not(necessarily(not(x2)))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by axiom 28 (and_3_1) }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(or(fresh3(fresh115(fresh40(fresh40(true, true, implies(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))))), true, implies(implies(and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), possibly(necessarily(not(x2)))), equiv(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))))), true, implies(and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), possibly(necessarily(not(x2)))), equiv(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))))), true, possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))), necessarily(not(necessarily(not(x2)))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by axiom 20 (modus_ponens_2) }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(or(fresh3(fresh115(fresh40(is_a_theorem(implies(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))))), true, implies(implies(and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), possibly(necessarily(not(x2)))), equiv(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))))), true, implies(and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), possibly(necessarily(not(x2)))), equiv(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))))), true, possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))), necessarily(not(necessarily(not(x2)))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by lemma 54 }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(or(fresh3(fresh115(true, true, implies(and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), possibly(necessarily(not(x2)))), equiv(possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))))), true, possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))), necessarily(not(necessarily(not(x2)))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by lemma 53 }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(or(fresh3(true, true, possibly(necessarily(not(x2))), and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))), necessarily(not(necessarily(not(x2)))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.06  = { by axiom 39 (substitution_of_equivalents_2) }
% 20.69/3.06    fresh74(fresh33(is_a_theorem(or(and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2)))), necessarily(not(necessarily(not(x2)))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by lemma 58 R->L }
% 20.69/3.07    fresh74(fresh33(is_a_theorem(implies(not(and(possibly(necessarily(not(x2))), possibly(necessarily(not(x2))))), necessarily(not(necessarily(not(x2)))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by lemma 59 R->L }
% 20.69/3.07    fresh74(fresh33(is_a_theorem(implies(not(and(possibly(necessarily(not(x2))), not(necessarily(not(necessarily(not(x2))))))), necessarily(not(necessarily(not(x2)))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by lemma 57 }
% 20.69/3.07    fresh74(fresh33(is_a_theorem(implies(implies(possibly(necessarily(not(x2))), necessarily(not(necessarily(not(x2))))), necessarily(not(necessarily(not(x2)))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by lemma 60 R->L }
% 20.69/3.07    fresh74(fresh33(is_a_theorem(implies(or(necessarily(not(necessarily(not(x2)))), necessarily(not(necessarily(not(x2))))), necessarily(not(necessarily(not(x2)))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by lemma 61 }
% 20.69/3.07    fresh74(fresh33(fresh59(cn3, true, necessarily(not(necessarily(not(x2))))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by lemma 59 }
% 20.69/3.07    fresh74(fresh33(fresh59(cn3, true, necessarily(possibly(x2))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by lemma 56 }
% 20.69/3.07    fresh74(fresh33(fresh59(cn3, true, possibly(x2)), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by lemma 61 R->L }
% 20.69/3.07    fresh74(fresh33(is_a_theorem(implies(or(possibly(x2), possibly(x2)), possibly(x2))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by axiom 20 (modus_ponens_2) R->L }
% 20.69/3.07    fresh74(fresh33(fresh40(true, true, implies(or(possibly(x2), possibly(x2)), possibly(x2))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by lemma 62 R->L }
% 20.69/3.07    fresh74(fresh33(fresh40(fresh40(is_a_theorem(implies(possibly(x2), implies(possibly(x2), possibly(x2)))), true, implies(possibly(x2), possibly(x2))), true, implies(or(possibly(x2), possibly(x2)), possibly(x2))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by axiom 40 (implies_1_1) R->L }
% 20.69/3.07    fresh74(fresh33(fresh40(fresh40(fresh51(implies_1, true, possibly(x2), possibly(x2)), true, implies(possibly(x2), possibly(x2))), true, implies(or(possibly(x2), possibly(x2)), possibly(x2))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by axiom 3 (hilbert_implies_1) }
% 20.69/3.07    fresh74(fresh33(fresh40(fresh40(fresh51(true, true, possibly(x2), possibly(x2)), true, implies(possibly(x2), possibly(x2))), true, implies(or(possibly(x2), possibly(x2)), possibly(x2))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by axiom 30 (implies_1_1) }
% 20.69/3.07    fresh74(fresh33(fresh40(fresh40(true, true, implies(possibly(x2), possibly(x2))), true, implies(or(possibly(x2), possibly(x2)), possibly(x2))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by axiom 20 (modus_ponens_2) }
% 20.69/3.07    fresh74(fresh33(fresh40(is_a_theorem(implies(possibly(x2), possibly(x2))), true, implies(or(possibly(x2), possibly(x2)), possibly(x2))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by axiom 47 (modus_ponens_2) R->L }
% 20.69/3.07    fresh74(fresh33(fresh115(is_a_theorem(implies(implies(possibly(x2), possibly(x2)), implies(or(possibly(x2), possibly(x2)), possibly(x2)))), true, implies(possibly(x2), possibly(x2)), implies(or(possibly(x2), possibly(x2)), possibly(x2))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by axiom 20 (modus_ponens_2) R->L }
% 20.69/3.07    fresh74(fresh33(fresh115(fresh40(true, true, implies(implies(possibly(x2), possibly(x2)), implies(or(possibly(x2), possibly(x2)), possibly(x2)))), true, implies(possibly(x2), possibly(x2)), implies(or(possibly(x2), possibly(x2)), possibly(x2))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by axiom 43 (or_3_1) R->L }
% 20.69/3.07    fresh74(fresh33(fresh115(fresh40(fresh17(true, true, possibly(x2), possibly(x2), possibly(x2)), true, implies(implies(possibly(x2), possibly(x2)), implies(or(possibly(x2), possibly(x2)), possibly(x2)))), true, implies(possibly(x2), possibly(x2)), implies(or(possibly(x2), possibly(x2)), possibly(x2))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by axiom 7 (hilbert_or_3) R->L }
% 20.69/3.07    fresh74(fresh33(fresh115(fresh40(fresh17(or_3, true, possibly(x2), possibly(x2), possibly(x2)), true, implies(implies(possibly(x2), possibly(x2)), implies(or(possibly(x2), possibly(x2)), possibly(x2)))), true, implies(possibly(x2), possibly(x2)), implies(or(possibly(x2), possibly(x2)), possibly(x2))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by axiom 52 (or_3_1) }
% 20.69/3.07    fresh74(fresh33(fresh115(fresh40(is_a_theorem(implies(implies(possibly(x2), possibly(x2)), implies(implies(possibly(x2), possibly(x2)), implies(or(possibly(x2), possibly(x2)), possibly(x2))))), true, implies(implies(possibly(x2), possibly(x2)), implies(or(possibly(x2), possibly(x2)), possibly(x2)))), true, implies(possibly(x2), possibly(x2)), implies(or(possibly(x2), possibly(x2)), possibly(x2))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by lemma 62 }
% 20.69/3.07    fresh74(fresh33(fresh115(true, true, implies(possibly(x2), possibly(x2)), implies(or(possibly(x2), possibly(x2)), possibly(x2))), true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by lemma 53 }
% 20.69/3.07    fresh74(fresh33(true, true, implies(possibly(possibly(x2)), possibly(x2))), true)
% 20.69/3.07  = { by axiom 22 (necessitation_1) }
% 20.69/3.07    fresh74(true, true)
% 20.69/3.07  = { by axiom 16 (axiom_m9) }
% 20.69/3.07    true
% 20.69/3.07  % SZS output end Proof
% 20.69/3.07  
% 20.69/3.07  RESULT: Theorem (the conjecture is true).
%------------------------------------------------------------------------------