Nuprl Lemma : not-quotient-function-subtype

¬(∀[X,A:Type]. ∀[E:A ⟶ A ⟶ ℙ].
    (EquivRel(A;a,b.E[a;b]) ⇒ ((X ⟶ (a,b:A//E[a;b])) ⊆r (f,g:X ⟶ A//fun-equiv(X;a,b.↓E[a;b];f;g)))))


Proof




Definitions occuring in Statement :  fun-equiv: fun-equiv(X;a,b.E[a; b];f;g),  equiv_rel: EquivRel(T;x,y.E[x; y]),  quotient: x,y:A//B[x; y],  subtype_rel: A ⊆r B,  uall: ∀[x:A]. B[x],  prop: ℙ,  so_apply: x[s1;s2],  not: ¬A,  squash: ↓T,  implies: P ⇒ Q,  function: x:A ⟶ B[x],  universe: Type
Definitions unfolded in proof :  not: ¬A,  implies: P ⇒ Q,  uall: ∀[x:A]. B[x],  member: t ∈ T,  prop: ℙ,  so_lambda: λ2x y.t[x; y],  so_apply: x[s1;s2],  uimplies: b supposing a,  subtype_rel: A ⊆r B,  quotient: x,y:A//B[x; y],  false: False,  and: P ∧ Q,  cand: A c∧ B,  all: ∀x:A. B[x],  true: True,  sq_type: SQType(T),  guard: {T}
Lemmas referenced :  istype-universe,  equiv_rel_wf,  subtype_rel_wf,  quotient_wf,  fun-equiv_wf,  base_wf,  true_wf,  istype-base,  equiv_rel_true,  squash_wf,  quotient-member-eq,  subtype_base_sq,  subtype_rel_self,  int_subtype_base,  fun-equiv-rel,  equiv_rel_squash,  quotient-squash
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  Error :lambdaFormation_alt,  sqequalRule,  Error :isectIsType,  cut,  instantiate,  introduction,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  universeEquality,  hypothesis,  Error :inhabitedIsType,  hypothesisEquality,  Error :functionIsType,  Error :universeIsType,  because_Cache,  Error :lambdaEquality_alt,  applyEquality,  functionEquality,  independent_isectElimination,  independent_functionElimination,  baseClosed,  equalityTransitivity,  equalitySymmetry,  pertypeElimination,  promote_hyp,  productElimination,  Error :productIsType,  Error :equalityIstype,  sqequalBase,  dependent_functionElimination,  natural_numberEquality,  cumulativity,  intEquality,  voidElimination

Latex:
\mneg{}(\mforall{}[X,A:Type].  \mforall{}[E:A  {}\mrightarrow{}  A  {}\mrightarrow{}  \mBbbP{}].
        (EquivRel(A;a,b.E[a;b])
        {}\mRightarrow{}  ((X  {}\mrightarrow{}  (a,b:A//E[a;b]))  \msubseteq{}r  (f,g:X  {}\mrightarrow{}  A//fun-equiv(X;a,b.\mdownarrow{}E[a;b];f;g)))))



Date html generated: 2019_06_20-PM-00_32_59
Last ObjectModification: 2018_11_26-AM-00_13_31

Theory : quot_1


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