Def A == A  False

is mentioned by

Thm* x,y:Atom. (x=yAtom ~ false)  x = y	[eq_atom_eq_false_elim_sqequal]
Thm* i,j:. ((i<j) ~ false)  i<j	[lt_int_eq_false_elim_sqequal]
Thm* x,y:Atom. x=yAtom = false  x = y	[eq_atom_eq_false_elim]
Thm* i,j:. (i<j) = false  i<j	[lt_int_eq_false_elim]
Thm* i,j:. i = j  ((i=j) ~ false)	[eq_int_eq_false_intro]

In prior sections: core bool 1

Try larger context: StandardLIB IF YOU CAN SEE THIS go to /sfa/Nuprl/Shared/Xindentation_hack_doc.html