## TPTP Problem File: SEV176^5.p

View Solutions - Solve Problem

```%------------------------------------------------------------------------------
% File     : SEV176^5 : TPTP v7.5.0. Released v4.0.0.
% Domain   : Set Theory
% Problem  : TPS problem THM25
% Version  : Especial.
% English  : Quine's modification of Russell's paradox.

% Refs     : [Bro09] Brown (2009), Email to Geoff Sutcliffe
% Source   : [Bro09]
% Names    : tps_0281 [Bro09]
%          : THM25 [TPS]

% Status   : Theorem
% Rating   : 0.08 v7.4.0, 0.11 v7.3.0, 0.10 v7.2.0, 0.12 v7.1.0, 0.14 v7.0.0, 0.12 v6.4.0, 0.14 v6.3.0, 0.17 v6.0.0, 0.00 v4.0.0
% Syntax   : Number of formulae    :    2 (   0 unit;   1 type;   0 defn)
%            Number of atoms       :    9 (   0 equality;   6 variable)
%            Maximal formula depth :   10 (   7 average)
%            Number of connectives :   10 (   2   ~;   0   |;   1   &;   6   @)
%                                         (   1 <=>;   0  =>;   0  <=;   0 <~>)
%                                         (   0  ~|;   0  ~&)
%            Number of type conns  :    2 (   2   >;   0   *;   0   +;   0  <<)
%            Number of symbols     :    3 (   1   :;   0   =)
%            Number of variables   :    3 (   0 sgn;   1   !;   2   ?;   0   ^)
%                                         (   3   :;   0  !>;   0  ?*)
%                                         (   0  @-;   0  @+)
% SPC      : TH0_THM_NEQ_NAR

% Comments : This problem is from the TPS library. Copyright (c) 2009 The TPS
%            project in the Department of Mathematical Sciences at Carnegie
%------------------------------------------------------------------------------
thf(cR,type,(
cR: \$i > \$i > \$o )).

thf(cTHM25,conjecture,(
~ ( ? [Y: \$i] :
! [X: \$i] :
( ( cR @ X @ Y )
<=> ~ ( ? [Z: \$i] :
( ( cR @ X @ Z )
& ( cR @ Z @ X ) ) ) ) ) )).

%------------------------------------------------------------------------------
```