Nuprl Lemma : equiv_rel_quotient

∀[T:Type]. ∀[E1,E2:T ⟶ T ⟶ 𝔹].
  (EquivRel(T;x,y.↑E2[x;y])
  ⇒ EquivRel(T;x,y.↑E1[x;y])
  ⇒ (∀x,y:T.  ((↑E2[x;y]) ⇒ (↑E1[x;y])))
  ⇒ EquivRel(x,y:T//(↑E2[x;y]);x,y.↑E1[x;y]))


Proof




Definitions occuring in Statement :  equiv_rel: EquivRel(T;x,y.E[x; y]),  quotient: x,y:A//B[x; y],  assert: ↑b,  bool: 𝔹,  uall: ∀[x:A]. B[x],  so_apply: x[s1;s2],  all: ∀x:A. B[x],  implies: P ⇒ Q,  function: x:A ⟶ B[x],  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  implies: P ⇒ Q,  member: t ∈ T,  equiv_rel: EquivRel(T;x,y.E[x; y]),  and: P ∧ Q,  refl: Refl(T;x,y.E[x; y]),  all: ∀x:A. B[x],  so_lambda: λ2x y.t[x; y],  so_apply: x[s1;s2],  uimplies: b supposing a,  cand: A c∧ B,  sym: Sym(T;x,y.E[x; y]),  prop: ℙ,  trans: Trans(T;x,y.E[x; y]),  so_lambda: λ2x.t[x],  so_apply: x[s],  quotient: x,y:A//B[x; y],  subtype_rel: A ⊆r B,  guard: {T}
Lemmas referenced :  equiv_rel-wf-quotient,  quotient_wf,  assert_wf,  assert_witness,  all_wf,  equiv_rel_wf,  bool_wf,  subtype_quotient,  equal-wf-base,  equal_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  lambdaFormation,  cut,  introduction,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesisEquality,  independent_functionElimination,  hypothesis,  independent_pairFormation,  cumulativity,  sqequalRule,  lambdaEquality,  applyEquality,  functionExtensionality,  independent_isectElimination,  because_Cache,  functionEquality,  universeEquality,  pointwiseFunctionalityForEquality,  pertypeElimination,  productElimination,  equalityTransitivity,  equalitySymmetry,  productEquality,  dependent_functionElimination,  rename

Latex:
\mforall{}[T:Type].  \mforall{}[E1,E2:T  {}\mrightarrow{}  T  {}\mrightarrow{}  \mBbbB{}].
    (EquivRel(T;x,y.\muparrow{}E2[x;y])
    {}\mRightarrow{}  EquivRel(T;x,y.\muparrow{}E1[x;y])
    {}\mRightarrow{}  (\mforall{}x,y:T.    ((\muparrow{}E2[x;y])  {}\mRightarrow{}  (\muparrow{}E1[x;y])))
    {}\mRightarrow{}  EquivRel(x,y:T//(\muparrow{}E2[x;y]);x,y.\muparrow{}E1[x;y]))



Date html generated: 2017_04_14-AM-07_39_44
Last ObjectModification: 2017_02_27-PM-03_12_30

Theory : quot_1


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