Nuprl Lemma : opt_wf

∀[T:Type]. ∀[x:T]. ∀[b:𝔹].  ((b?x) ∈ T?)


Proof




Definitions occuring in Statement :  opt: (b?x),  bool: 𝔹,  uall: ∀[x:A]. B[x],  unit: Unit,  member: t ∈ T,  union: left + right,  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  opt: (b?x),  all: ∀x:A. B[x],  implies: P ⇒ Q,  exposed-bfalse: exposed-bfalse,  bool: 𝔹,  unit: Unit,  it: ⋅,  btrue: tt,  uiff: uiff(P;Q),  and: P ∧ Q,  uimplies: b supposing a,  ifthenelse: if b then t else f fi ,  bfalse: ff,  prop: ℙ
Lemmas referenced :  eqtt_to_assert,  unit_wf2,  uiff_transitivity,  equal-wf-T-base,  bool_wf,  assert_wf,  bnot_wf,  not_wf,  eqff_to_assert,  assert_of_bnot,  it_wf,  equal_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation_alt,  introduction,  cut,  sqequalRule,  hypothesisEquality,  thin,  because_Cache,  lambdaFormation,  sqequalHypSubstitution,  unionElimination,  equalityElimination,  extract_by_obid,  isectElimination,  hypothesis,  productElimination,  independent_isectElimination,  inlEquality,  baseClosed,  independent_functionElimination,  inrEquality,  equalityTransitivity,  equalitySymmetry,  dependent_functionElimination,  axiomEquality,  universeIsType,  isect_memberEquality,  universeEquality

Latex:
\mforall{}[T:Type].  \mforall{}[x:T].  \mforall{}[b:\mBbbB{}].    ((b?x)  \mmember{}  T?)



Date html generated: 2019_10_15-AM-10_46_43
Last ObjectModification: 2018_09_27-AM-09_37_27

Theory : basic


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