## TPTP Axioms File: SET006+3.ax

```%------------------------------------------------------------------------------
% File     : SET006+3 : TPTP v7.5.0. Released v3.2.0.
% Domain   : Set Theory
% Axioms   : Order relation (Naive set theory)
% Version  : [Pas05] axioms.
% English  :

% Refs     : [Pas05] Pastre (2005), Email to G. Sutcliffe
% Source   : [Pas05]
% Names    :

% Status   : Satisfiable
% Syntax   : Number of formulae    :   10 (   0 unit)
%            Number of atoms       :   56 (   3 equality)
%            Maximal formula depth :   12 (   9 average)
%            Number of connectives :   46 (   0 ~  ;   1  |;  21  &)
%                                         (  10 <=>;  14 =>;   0 <=)
%                                         (   0 <~>;   0 ~|;   0 ~&)
%            Number of predicates  :   13 (   0 propositional; 2-4 arity)
%            Number of functors    :    0 (   0 constant; --- arity)
%            Number of variables   :   46 (   0 singleton;  46 !;   0 ?)
%            Maximal term depth    :    1 (   1 average)
% SPC      :

%------------------------------------------------------------------------------
%----Order relations
fof(order,axiom,(
! [R,E] :
( order(R,E)
<=> ( ! [X] :
( member(X,E)
=> apply(R,X,X) )
& ! [X,Y] :
( ( member(X,E)
& member(Y,E) )
=> ( ( apply(R,X,Y)
& apply(R,Y,X) )
=> X = Y ) )
& ! [X,Y,Z] :
( ( member(X,E)
& member(Y,E)
& member(Z,E) )
=> ( ( apply(R,X,Y)
& apply(R,Y,Z) )
=> apply(R,X,Z) ) ) ) ) )).

fof(total_order,axiom,(
! [R,E] :
( total_order(R,E)
<=> ( order(R,E)
& ! [X,Y] :
( ( member(X,E)
& member(Y,E) )
=> ( apply(R,X,Y)
| apply(R,Y,X) ) ) ) ) )).

fof(upper_bound,axiom,(
! [R,E,M] :
( upper_bound(M,R,E)
<=> ! [X] :
( member(X,E)
=> apply(R,X,M) ) ) )).

fof(lower_bound,axiom,(
! [R,E,M] :
( lower_bound(M,R,E)
<=> ! [X] :
( member(X,E)
=> apply(R,M,X) ) ) )).

fof(greatest,axiom,(
! [R,E,M] :
( greatest(M,R,E)
<=> ( member(M,E)
& ! [X] :
( member(X,E)
=> apply(R,X,M) ) ) ) )).

fof(least,axiom,(
! [R,E,M] :
( least(M,R,E)
<=> ( member(M,E)
& ! [X] :
( member(X,E)
=> apply(R,M,X) ) ) ) )).

fof(max,axiom,(
! [R,E,M] :
( max(M,R,E)
<=> ( member(M,E)
& ! [X] :
( ( member(X,E)
& apply(R,M,X) )
=> M = X ) ) ) )).

fof(min,axiom,(
! [R,E,M] :
( min(M,R,E)
<=> ( member(M,E)
& ! [X] :
( ( member(X,E)
& apply(R,X,M) )
=> M = X ) ) ) )).

fof(least_upper_bound,axiom,(
! [A,X,R,E] :
( least_upper_bound(A,X,R,E)
<=> ( member(A,X)
& upper_bound(A,R,X)
& ! [M] :
( ( member(M,E)
& upper_bound(M,R,X) )
=> apply(R,A,M) ) ) ) )).

fof(greatest_lower_bound,axiom,(
! [A,X,R,E] :
( greatest_lower_bound(A,X,R,E)
<=> ( member(A,X)
& lower_bound(A,R,X)
& ! [M] :
( ( member(M,E)
& lower_bound(M,R,X) )
=> apply(R,M,A) ) ) ) )).

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