Def one_el == 

is mentioned by

Thm* 'a:S. all(e:'a. exists_unique(fn:hone  'a. equal(fn(one_el),e)))	[hone_axiom_2]
Thm* all(v:hone. equal(v,one_el))	[hone_wd]
Thm* equal(one_el,select(x:hone. t))	[hone_def]

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