TPTP Axioms File: LDA001-0.ax
%--------------------------------------------------------------------------
% File : LDA001-0 : TPTP v9.0.0. Bugfixed v2.6.0.
% Domain : LD-Algebras (Embedding algebras)
% Axioms : Embedding algebra
% Version : [Jec93] axioms : Incomplete.
% English : LD-algebras are related to large cardinals. Under a very
% strong large cardinal assumption, the free-monogenic
% LD-algebra can be represented by an algebra of elementary
% embeddings. Theorems about this algebra can be proved from
% a small number of properties, suggesting the definition
% of an embedding algebra.
% Refs : [Jec93] Jech (1993), LD-Algebras
% : [Jec02] Jech (2002), Email to Geoff Sutcliffe
% Source : [Jec93]
% Names :
% Status : Satisfiable
% Syntax : Number of clauses : 9 ( 4 unt; 2 nHn; 3 RR)
% Number of literals : 16 ( 5 equ; 5 neg)
% Maximal clause size : 3 ( 1 avg)
% Maximal term depth : 3 ( 1 avg)
% Number of predicates : 2 ( 1 usr; 0 prp; 2-2 aty)
% Number of functors : 3 ( 3 usr; 0 con; 1-2 aty)
% Number of variables : 21 ( 0 sgn)
% SPC :
% Comments : [Jec93] says, "Even though axioms for embedding algebras
% include additional properties to those listed below, many
% results can be proved from these axioms."
% Bugfixes : v2.6.0 - Fixed axioms; they were unsatisfiable [Jec02]
%--------------------------------------------------------------------------
%----A1 x(yz)=(xy)(xz)
cnf(a1,axiom,
f(X,f(Y,Z)) = f(f(X,Y),f(X,Z)) ).
%----A1a a(x,a(y,z)) = a(x*y,a(x,z))
cnf(a1a,axiom,
a(X,a(Y,Z)) = a(f(X,Y),a(X,Z)) ).
%----A2 cr(u*v) = a(u,cr(v))
cnf(a2,axiom,
critical_point(f(U,V)) = a(U,critical_point(V)) ).
%----B1 -(x<x)
cnf(b1,axiom,
~ less(X,X) ).
%----B2 linear
cnf(b2,axiom,
( less(X,Y)
| less(Y,X)
| X = Y ) ).
%----B3 transitive
cnf(b3,axiom,
( ~ less(X,Y)
| ~ less(Y,Z)
| less(X,Z) ) ).
%----B4 if x<y then ux<uy
cnf(b4,axiom,
( ~ less(X,Y)
| less(a(U,X),a(U,Y)) ) ).
%----C2 if x<crit(u) then ux=x
cnf(c2,axiom,
( ~ less(X,critical_point(U))
| a(U,X) = X ) ).
%----C3 x<crit(u) or x<ux
cnf(c3,axiom,
( less(X,critical_point(U))
| less(X,a(U,X)) ) ).
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