TSTP Solution File: SET050-6 by Twee---2.4.2

View Problem - Process Solution

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% File     : Twee---2.4.2
% Problem  : SET050-6 : TPTP v8.1.2. Bugfixed v2.1.0.
% 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 : n006.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 15:30:52 EDT 2023

% Result   : Unsatisfiable 0.19s 0.56s
% Output   : Proof 0.19s
% Verified : 
% SZS Type : -

% Comments : 
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%----WARNING: Could not form TPTP format derivation
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%----ORIGINAL SYSTEM OUTPUT
% 0.00/0.12  % Problem  : SET050-6 : TPTP v8.1.2. Bugfixed v2.1.0.
% 0.00/0.13  % Command  : parallel-twee %s --tstp --conditional-encoding if --smaller --drop-non-horn --give-up-on-saturation --explain-encoding --formal-proof
% 0.12/0.34  % Computer : n006.cluster.edu
% 0.12/0.34  % Model    : x86_64 x86_64
% 0.12/0.34  % CPU      : Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz
% 0.12/0.34  % Memory   : 8042.1875MB
% 0.12/0.34  % OS       : Linux 3.10.0-693.el7.x86_64
% 0.12/0.34  % CPULimit : 300
% 0.12/0.34  % WCLimit  : 300
% 0.12/0.34  % DateTime : Sat Aug 26 10:21:22 EDT 2023
% 0.12/0.34  % CPUTime  : 
% 0.19/0.56  Command-line arguments: --no-flatten-goal
% 0.19/0.56  
% 0.19/0.56  % SZS status Unsatisfiable
% 0.19/0.56  
% 0.19/0.57  % SZS output start Proof
% 0.19/0.57  Take the following subset of the input axioms:
% 0.19/0.57    fof(cartesian_product1, axiom, ![X, Y, U, V]: (~member(ordered_pair(U, V), cross_product(X, Y)) | member(U, X))).
% 0.19/0.57    fof(class_elements_are_sets, axiom, ![X2]: subclass(X2, universal_class)).
% 0.19/0.57    fof(prove_corollary_1_to_unordered_pair_1, negated_conjecture, member(ordered_pair(x, y), cross_product(u, v))).
% 0.19/0.57    fof(prove_corollary_1_to_unordered_pair_2, negated_conjecture, ~member(x, unordered_pair(x, y))).
% 0.19/0.57    fof(subclass_members, axiom, ![X2, Y2, U2]: (~subclass(X2, Y2) | (~member(U2, X2) | member(U2, Y2)))).
% 0.19/0.57    fof(unordered_pair2, axiom, ![X2, Y2]: (~member(X2, universal_class) | member(X2, unordered_pair(X2, Y2)))).
% 0.19/0.57  
% 0.19/0.57  Now clausify the problem and encode Horn clauses using encoding 3 of
% 0.19/0.57  http://www.cse.chalmers.se/~nicsma/papers/horn.pdf.
% 0.19/0.57  We repeatedly replace C & s=t => u=v by the two clauses:
% 0.19/0.57    fresh(y, y, x1...xn) = u
% 0.19/0.57    C => fresh(s, t, x1...xn) = v
% 0.19/0.57  where fresh is a fresh function symbol and x1..xn are the free
% 0.19/0.57  variables of u and v.
% 0.19/0.57  A predicate p(X) is encoded as p(X)=true (this is sound, because the
% 0.19/0.57  input problem has no model of domain size 1).
% 0.19/0.57  
% 0.19/0.57  The encoding turns the above axioms into the following unit equations and goals:
% 0.19/0.57  
% 0.19/0.57  Axiom 1 (class_elements_are_sets): subclass(X, universal_class) = true2.
% 0.19/0.57  Axiom 2 (cartesian_product1): fresh63(X, X, Y, Z) = true2.
% 0.19/0.57  Axiom 3 (subclass_members): fresh10(X, X, Y, Z) = true2.
% 0.19/0.57  Axiom 4 (unordered_pair2): fresh6(X, X, Y, Z) = true2.
% 0.19/0.57  Axiom 5 (subclass_members): fresh11(X, X, Y, Z, W) = member(W, Z).
% 0.19/0.57  Axiom 6 (unordered_pair2): fresh6(member(X, universal_class), true2, X, Y) = member(X, unordered_pair(X, Y)).
% 0.19/0.57  Axiom 7 (prove_corollary_1_to_unordered_pair_1): member(ordered_pair(x, y), cross_product(u, v)) = true2.
% 0.19/0.57  Axiom 8 (subclass_members): fresh11(member(X, Y), true2, Y, Z, X) = fresh10(subclass(Y, Z), true2, Z, X).
% 0.19/0.57  Axiom 9 (cartesian_product1): fresh63(member(ordered_pair(X, Y), cross_product(Z, W)), true2, X, Z) = member(X, Z).
% 0.19/0.57  
% 0.19/0.57  Goal 1 (prove_corollary_1_to_unordered_pair_2): member(x, unordered_pair(x, y)) = true2.
% 0.19/0.57  Proof:
% 0.19/0.57    member(x, unordered_pair(x, y))
% 0.19/0.57  = { by axiom 6 (unordered_pair2) R->L }
% 0.19/0.57    fresh6(member(x, universal_class), true2, x, y)
% 0.19/0.57  = { by axiom 5 (subclass_members) R->L }
% 0.19/0.57    fresh6(fresh11(true2, true2, u, universal_class, x), true2, x, y)
% 0.19/0.57  = { by axiom 2 (cartesian_product1) R->L }
% 0.19/0.57    fresh6(fresh11(fresh63(true2, true2, x, u), true2, u, universal_class, x), true2, x, y)
% 0.19/0.57  = { by axiom 7 (prove_corollary_1_to_unordered_pair_1) R->L }
% 0.19/0.57    fresh6(fresh11(fresh63(member(ordered_pair(x, y), cross_product(u, v)), true2, x, u), true2, u, universal_class, x), true2, x, y)
% 0.19/0.57  = { by axiom 9 (cartesian_product1) }
% 0.19/0.57    fresh6(fresh11(member(x, u), true2, u, universal_class, x), true2, x, y)
% 0.19/0.57  = { by axiom 8 (subclass_members) }
% 0.19/0.57    fresh6(fresh10(subclass(u, universal_class), true2, universal_class, x), true2, x, y)
% 0.19/0.57  = { by axiom 1 (class_elements_are_sets) }
% 0.19/0.57    fresh6(fresh10(true2, true2, universal_class, x), true2, x, y)
% 0.19/0.57  = { by axiom 3 (subclass_members) }
% 0.19/0.57    fresh6(true2, true2, x, y)
% 0.19/0.57  = { by axiom 4 (unordered_pair2) }
% 0.19/0.57    true2
% 0.19/0.57  % SZS output end Proof
% 0.19/0.57  
% 0.19/0.57  RESULT: Unsatisfiable (the axioms are contradictory).
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