Some definitions of interest.
xmiddle	Def XM == P:Prop. Dec(P)
	Thm* XM{i}  Prop{i'}
not	Def A == A  False
	Thm* A:Prop. (A)  Prop
stype	Def S == {T:Type| x:T. True }
	Thm* S  Type{2}

About: IF YOU CAN SEE THIS go to /sfa/Nuprl/Shared/Xindentation_hack_doc.html