TPTP Problem File: LCL634^1.p
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% File : LCL634^1 : TPTP v9.0.0. Bugfixed v5.2.0.
% Domain : Logical Calculi
% Problem : Goedel's ontological argument on the existence of God
% Version : [Ben08] axioms.
% English :
% Refs : [Fit00] Fitting (2000), Higher-Order Modal Logic - A Sketch
% : [Ben08] Benzmueller (2008), Email to G. Sutcliffe
% Source : [Ben08]
% Names : Fitting-HOLML-Ex-God-alternative-b [Ben08]
% Status : CounterSatisfiable
% Rating : 0.67 v9.0.0, 1.00 v8.1.0, 0.80 v7.4.0, 0.75 v7.2.0, 0.67 v5.4.0, 1.00 v5.2.0
% Syntax : Number of formulae : 26 ( 10 unt; 12 typ; 9 def)
% Number of atoms : 48 ( 9 equ; 0 cnn)
% Maximal formula atoms : 7 ( 3 avg)
% Number of connectives : 64 ( 1 ~; 1 |; 1 &; 58 @)
% ( 0 <=>; 3 =>; 0 <=; 0 <~>)
% Maximal formula depth : 9 ( 3 avg)
% Number of types : 3 ( 1 usr)
% Number of type conns : 69 ( 69 >; 0 *; 0 +; 0 <<)
% Number of symbols : 12 ( 11 usr; 0 con; 1-3 aty)
% Number of variables : 34 ( 24 ^; 10 !; 0 ?; 34 :)
% SPC : TH0_CSA_EQU_NAR
% Comments :
% Bugfixes : v4.0.0 - Complete overhaul.
% : v5.2.0 - Added missing types
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%----Some higher-order multimodal operators are needed
%----Base type individuals; corresponds to type 0 in [Fit00]
thf(individuals_decl,type,
individuals: $tType ).
thf(e_type,type,
e: ( individuals > $i > $o ) > individuals > $i > $o ).
thf(g_type,type,
g: individuals > $i > $o ).
thf(mall_ind_type,type,
mall_ind: ( individuals > $i > $o ) > $i > $o ).
thf(mall_indset_type,type,
mall_indset: ( ( individuals > $i > $o ) > $i > $o ) > $i > $o ).
thf(mbox_type,type,
mbox: ( $i > $i > $o ) > ( $i > $o ) > $i > $o ).
thf(mimplies_type,type,
mimplies: ( $i > $o ) > ( $i > $o ) > $i > $o ).
thf(mnot_type,type,
mnot: ( $i > $o ) > $i > $o ).
thf(mor_type,type,
mor: ( $i > $o ) > ( $i > $o ) > $i > $o ).
thf(mvalid_type,type,
mvalid: ( $i > $o ) > $o ).
%----mnot corresponds to set complement
thf(mnot,definition,
( mnot
= ( ^ [Phi: $i > $o,W: $i] :
~ ( Phi @ W ) ) ) ).
thf(mor,definition,
( mor
= ( ^ [Phi: $i > $o,Psi: $i > $o,W: $i] :
( ( Phi @ W )
| ( Psi @ W ) ) ) ) ).
%----mimplies defined via mnot and mor
thf(mimplies,definition,
( mimplies
= ( ^ [Phi: $i > $o,Psi: $i > $o] : ( mor @ ( mnot @ Phi ) @ Psi ) ) ) ).
%----mbox
thf(mbox,definition,
( mbox
= ( ^ [R: $i > $i > $o,Phi: $i > $o,W: $i] :
! [U: $i] :
( ( R @ W @ U )
=> ( Phi @ U ) ) ) ) ).
%----mall_ind (for individuals)
thf(mall_ind,definition,
( mall_ind
= ( ^ [Phi: individuals > $i > $o,W: $i] :
! [X: individuals] : ( Phi @ X @ W ) ) ) ).
%----mall_indset (for sets of individuals)
thf(mall_indset,definition,
( mall_indset
= ( ^ [Phi: ( individuals > $i > $o ) > $i > $o,W: $i] :
! [X: individuals > $i > $o] : ( Phi @ X @ W ) ) ) ).
%----Validity of a multi modal logic formula can now be encoded as
thf(mvalid,definition,
( mvalid
= ( ^ [Phi: $i > $o] :
! [W: $i] : ( Phi @ W ) ) ) ).
%----The encoding of the example
%----r is an S5 accessibility relation: reflexive, transitive and symmetric
thf(r_type,type,
r: $i > $i > $o ).
thf(r_refl,axiom,
! [X: $i] : ( r @ X @ X ) ).
thf(r_trans,axiom,
! [X: $i,Y: $i,Z: $i] :
( ( ( r @ X @ Y )
& ( r @ Y @ Z ) )
=> ( r @ X @ Z ) ) ).
thf(r_sym,axiom,
! [X: $i,Y: $i] :
( ( r @ X @ Y )
=> ( r @ Y @ X ) ) ).
%----The axioms of the example
%----Positiveness: p
thf(p_type,type,
p: ( individuals > $i > $o ) > $i > $o ).
thf(positiveness,axiom,
( mvalid
@ ( mall_indset
@ ^ [X: individuals > $i > $o] :
( mimplies @ ( mnot @ ( p @ X ) )
@ ( p
@ ^ [Z: individuals] : ( mnot @ ( X @ Z ) ) ) ) ) ) ).
%----Being God: g
thf(g,definition,
( g
= ( ^ [Z: individuals] :
( mall_indset
@ ^ [X: individuals > $i > $o] : ( mimplies @ ( p @ X ) @ ( X @ Z ) ) ) ) ) ).
%----Essence: e
thf(e,definition,
( e
= ( ^ [X: individuals > $i > $o,Z: individuals] :
( mall_indset
@ ^ [Y: individuals > $i > $o] :
( mimplies @ ( Y @ Z )
@ ( mbox @ r
@ ( mall_ind
@ ^ [U: individuals] : ( mimplies @ ( X @ U ) @ ( Y @ U ) ) ) ) ) ) ) ) ).
%----Conjecture: Being God is the essence of anything that is, in fact, God.
thf(thm,conjecture,
( mvalid
@ ( mall_ind
@ ^ [Z: individuals] : ( mimplies @ ( g @ Z ) @ ( e @ g @ Z ) ) ) ) ).
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