Nuprl Theory quot_1

COMquot_1_begin************ QUOT_1 ************
COMquot_1_summarySupport lemmas for quotient type.
COMquot_1_introBasic support for quotient type.
THMquotient_wfT:. E:T T . EquivRel(T;x,y.E[x;y]) x,y:T//E[x;y]
THMquotient_qincT:. E:T T . EquivRel(T;x,y.E[x;y]) T x,y:T//E[x;y]
THMtype_inj_wf_for_quotT:. E:T T . EquivRel(T;x,y.E[x;y]) (a:T. [a]{x,y:T//E[x;y]} x,y:T//E[x;y])
THMquot_elimT:. E:T T . EquivRel(T;x,y.E[x;y]) (a,b:T. a = b E[a;b])
THMall_quot_elimT:. E:T T . EquivRel(T;x,y.E[x;y]) (F:x,y:T//E[x;y] (w:x,y:T//E[x;y]. SqStable(F w)) ((z:x,y:T//E[x;y]. F[z]) (z:T. F[z])))
THMdec_iff_ex_bvfunT:. E:T T . (x,y:T. Dec(E[x;y])) (f:T T . x,y:T. (x f y) E[x;y])
THMdecidable__quotient_equalT:. E:T T . EquivRel(T;x,y.E[x;y]) (x,y:T. Dec(E[x;y])) (u,v:x,y:T//E[x;y]. Dec(u = v))
COMquot_1_end********************************