Nuprl Lemma : stable-union_wf

∀[X,T:Type]. ∀[P:T ⟶ X ⟶ ℙ].  (stable-union(X;T;i,x.P[i;x]) ∈ Type)


Proof




Definitions occuring in Statement :  stable-union: stable-union(X;T;i,x.P[i; x]),  uall: ∀[x:A]. B[x],  prop: ℙ,  so_apply: x[s1;s2],  member: t ∈ T,  function: x:A ⟶ B[x],  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  stable-union: stable-union(X;T;i,x.P[i; x]),  prop: ℙ,  exists: ∃x:A. B[x],  so_apply: x[s1;s2]
Lemmas referenced :  not_wf,  istype-universe
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation_alt,  introduction,  cut,  sqequalRule,  setEquality,  hypothesisEquality,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  productEquality,  applyEquality,  hypothesis,  axiomEquality,  equalityTransitivity,  equalitySymmetry,  functionIsType,  universeIsType,  universeEquality,  isect_memberEquality_alt,  isectIsTypeImplies,  inhabitedIsType,  instantiate

Latex:
\mforall{}[X,T:Type].  \mforall{}[P:T  {}\mrightarrow{}  X  {}\mrightarrow{}  \mBbbP{}].    (stable-union(X;T;i,x.P[i;x])  \mmember{}  Type)



Date html generated: 2020_05_19-PM-09_36_15
Last ObjectModification: 2019_10_24-AM-09_55_58

Theory : int_1


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