IF YOU CAN SEE THIS go to http://www.cs.cornell.edu/Info/People/sfa/Nuprl/Shared/Xindentation_hack_doc.html
At:
list-set-type2 T:Type, L:T List, P:(TProp). (xL.P(x)) L {x:T| P(x) } List
By:
Auto THEN Inst Thm*L:T List. L {x:T| (xL) } List [T;L] THEN DoSubsume
THEN
UseSubtypeRelLemmas