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:  Q function: x:A ⟶ B[x] universe: Type
Definitions unfolded in proof :  uall: [x:A]. B[x] implies:  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: λ2y.t[x; y] so_apply: x[s1;s2] uimplies: supposing a cand: c∧ B sym: Sym(T;x,y.E[x; y]) prop: 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 ⊆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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