Nuprl Lemma : per-union-implies-wf1

∀[A,B:Type]. ∀[x:per-union(A;B)].  (x ~ inl outl(x) ∈ ℙ)


Proof




Definitions occuring in Statement :  per-union: per-union(A;B),  outl: outl(x),  uall: ∀[x:A]. B[x],  prop: ℙ,  member: t ∈ T,  inl: inl x,  universe: Type,  sqequal: s ~ t
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  squash: ↓T,  prop: ℙ,  iff: P ⇐⇒ Q,  and: P ∧ Q,  implies: P ⇒ Q,  uimplies: b supposing a,  per-union: per-union(A;B),  has-value: (a)↓,  outl: outl(x),  uand: uand(A;B),  guard: {T},  top: Top,  outr: outr(x),  sq_type: SQType(T),  all: ∀x:A. B[x],  rev_implies: P ⇐ Q,  true: True
Lemmas referenced :  sqequal-wf-base,  member_wf,  subtype_base_sq,  subtype_rel_self,  has-value_wf_base,  is-exception_wf,  cbv-sqequal0,  istype-top,  istype-void,  uand_wf,  equal-wf-base,  per-void_wf,  istype-sqequal,  per-union_wf,  istype-universe,  if-per-void
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  Error :isect_memberFormation_alt,  cut,  pointwiseFunctionality,  introduction,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesisEquality,  sqequalRule,  baseApply,  closedConclusion,  baseClosed,  hypothesis,  applyEquality,  instantiate,  Error :lambdaEquality_alt,  imageElimination,  because_Cache,  universeEquality,  sqequalExtensionalEquality,  independent_pairFormation,  Error :lambdaFormation_alt,  independent_isectElimination,  pertypeElimination,  promote_hyp,  axiomSqleEquality,  divergentSqle,  sqleReflexivity,  isinlCases,  axiomSqEquality,  Error :inhabitedIsType,  Error :isect_memberEquality_alt,  Error :isectIsTypeImplies,  voidElimination,  Error :universeIsType,  isectEquality,  isinrCases,  dependent_functionElimination,  equalityTransitivity,  equalitySymmetry,  independent_functionElimination,  imageMemberEquality,  natural_numberEquality,  rename,  isaxiomCases

Latex:
\mforall{}[A,B:Type].  \mforall{}[x:per-union(A;B)].    (x  \msim{}  inl  outl(x)  \mmember{}  \mBbbP{})



Date html generated: 2019_06_20-AM-11_30_43
Last ObjectModification: 2019_01_03-PM-03_54_29

Theory : per!type


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