%------------------------------------------------------------------------------
% File     : Twee---2.4.2
% Problem  : GEO207+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 : n029.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 : Wed Aug 30 23:28:03 EDT 2023

% Result   : Theorem 0.21s 0.39s
% Output   : Proof 0.21s
% Verified : 
% SZS Type : -

% Comments : 
%------------------------------------------------------------------------------
%----WARNING: Could not form TPTP format derivation
%------------------------------------------------------------------------------
%----ORIGINAL SYSTEM OUTPUT
% 0.11/0.12  % Problem  : GEO207+1 : TPTP v8.1.2. Released v3.3.0.
% 0.11/0.13  % Command  : parallel-twee %s --tstp --conditional-encoding if --smaller --drop-non-horn --give-up-on-saturation --explain-encoding --formal-proof
% 0.14/0.35  % Computer : n029.cluster.edu
% 0.14/0.35  % Model    : x86_64 x86_64
% 0.14/0.35  % CPU      : Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz
% 0.14/0.35  % Memory   : 8042.1875MB
% 0.14/0.35  % OS       : Linux 3.10.0-693.el7.x86_64
% 0.14/0.35  % CPULimit : 300
% 0.14/0.35  % WCLimit  : 300
% 0.14/0.35  % DateTime : Tue Aug 29 20:59:57 EDT 2023
% 0.14/0.35  % CPUTime  : 
% 0.21/0.39  Command-line arguments: --set-join --lhs-weight 1 --no-flatten-goal --complete-subsets --goal-heuristic
% 0.21/0.39  
% 0.21/0.39  % SZS status Theorem
% 0.21/0.39  
% 0.21/0.39  % SZS output start Proof
% 0.21/0.39  Take the following subset of the input axioms:
% 0.21/0.39    fof(apart1, axiom, ![X]: ~distinct_points(X, X)).
% 0.21/0.39    fof(apart2, axiom, ![X2]: ~distinct_lines(X2, X2)).
% 0.21/0.39    fof(apart3, axiom, ![X2]: ~convergent_lines(X2, X2)).
% 0.21/0.39    fof(ci1, axiom, ![Y, X2]: (distinct_points(X2, Y) => ~apart_point_and_line(X2, line_connecting(X2, Y)))).
% 0.21/0.39    fof(ci2, axiom, ![X2, Y2]: (distinct_points(X2, Y2) => ~apart_point_and_line(Y2, line_connecting(X2, Y2)))).
% 0.21/0.39    fof(ci3, axiom, ![X2, Y2]: (convergent_lines(X2, Y2) => ~apart_point_and_line(intersection_point(X2, Y2), X2))).
% 0.21/0.39    fof(ci4, axiom, ![X2, Y2]: (convergent_lines(X2, Y2) => ~apart_point_and_line(intersection_point(X2, Y2), Y2))).
% 0.21/0.39    fof(con, conjecture, ![X2]: ~convergent_lines(X2, X2)).
% 0.21/0.39    fof(cp1, axiom, ![X2, Y2]: ~convergent_lines(parallel_through_point(Y2, X2), Y2)).
% 0.21/0.39    fof(cp2, axiom, ![X2, Y2]: ~apart_point_and_line(X2, parallel_through_point(Y2, X2))).
% 0.21/0.39  
% 0.21/0.39  Now clausify the problem and encode Horn clauses using encoding 3 of
% 0.21/0.39  http://www.cse.chalmers.se/~nicsma/papers/horn.pdf.
% 0.21/0.39  We repeatedly replace C & s=t => u=v by the two clauses:
% 0.21/0.39    fresh(y, y, x1...xn) = u
% 0.21/0.39    C => fresh(s, t, x1...xn) = v
% 0.21/0.39  where fresh is a fresh function symbol and x1..xn are the free
% 0.21/0.39  variables of u and v.
% 0.21/0.39  A predicate p(X) is encoded as p(X)=true (this is sound, because the
% 0.21/0.39  input problem has no model of domain size 1).
% 0.21/0.39  
% 0.21/0.39  The encoding turns the above axioms into the following unit equations and goals:
% 0.21/0.39  
% 0.21/0.39  Axiom 1 (con): convergent_lines(x, x) = true2.
% 0.21/0.39  
% 0.21/0.39  Goal 1 (apart3): convergent_lines(X, X) = true2.
% 0.21/0.39  The goal is true when:
% 0.21/0.39    X = x
% 0.21/0.39  
% 0.21/0.39  Proof:
% 0.21/0.39    convergent_lines(x, x)
% 0.21/0.39  = { by axiom 1 (con) }
% 0.21/0.39    true2
% 0.21/0.39  % SZS output end Proof
% 0.21/0.39  
% 0.21/0.39  RESULT: Theorem (the conjecture is true).
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