Nuprl Lemma : Wmul-Wzero

∀[A:Type]. ∀[B:A ⟶ Type]. ∀[zero,succ:A ⟶ 𝔹].
  ∀[z:W(A;a.B[a])]. ∀[w1:W(A;a.B[a])]. ((w1 * z) = z ∈ W(A;a.B[a])) supposing isZero(z) 
  supposing ∀a:A. ((↑(succ a)) ⇒ (Unit ⊆r B[a]))


Proof




Definitions occuring in Statement :  Wmul: (w1 * w2),  Wzero: isZero(w),  W: W(A;a.B[a]),  assert: ↑b,  bool: 𝔹,  uimplies: b supposing a,  subtype_rel: A ⊆r B,  uall: ∀[x:A]. B[x],  so_apply: x[s],  all: ∀x:A. B[x],  implies: P ⇒ Q,  unit: Unit,  apply: f a,  function: x:A ⟶ B[x],  universe: Type,  equal: s = t ∈ T
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  uimplies: b supposing a,  so_lambda: λ2x.t[x],  so_apply: x[s],  implies: P ⇒ Q,  prop: ℙ,  all: ∀x:A. B[x],  Wsup: Wsup(a;b),  Wzero: isZero(w),  pi1: fst(t),  Wmul: (w1 * w2),  bool: 𝔹,  unit: Unit,  it: ⋅,  btrue: tt,  uiff: uiff(P;Q),  and: P ∧ Q,  ifthenelse: if b then t else f fi ,  not: ¬A,  subtype_rel: A ⊆r B,  false: False,  bfalse: ff,  exists: ∃x:A. B[x],  or: P ∨ Q,  sq_type: SQType(T),  guard: {T},  bnot: ¬bb,  assert: ↑b,  squash: ↓T,  true: True
Lemmas referenced :  W-induction,  Wzero_wf,  all_wf,  W_wf,  equal_wf,  Wmul_wf,  bool_wf,  eqtt_to_assert,  it_wf,  eqff_to_assert,  bool_cases_sqequal,  subtype_base_sq,  bool_subtype_base,  assert-bnot,  Wsup_wf,  squash_wf,  true_wf,  not_wf,  assert_wf,  subtype_rel_wf,  unit_wf2
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  thin,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  hypothesisEquality,  sqequalRule,  lambdaEquality,  applyEquality,  functionExtensionality,  cumulativity,  functionEquality,  because_Cache,  hypothesis,  independent_isectElimination,  independent_functionElimination,  lambdaFormation,  unionElimination,  equalityElimination,  equalityTransitivity,  equalitySymmetry,  productElimination,  dependent_functionElimination,  voidElimination,  dependent_pairFormation,  promote_hyp,  instantiate,  imageElimination,  natural_numberEquality,  imageMemberEquality,  baseClosed,  isect_memberEquality,  axiomEquality,  universeEquality

Latex:
\mforall{}[A:Type].  \mforall{}[B:A  {}\mrightarrow{}  Type].  \mforall{}[zero,succ:A  {}\mrightarrow{}  \mBbbB{}].
    \mforall{}[z:W(A;a.B[a])].  \mforall{}[w1:W(A;a.B[a])].  ((w1  *  z)  =  z)  supposing  isZero(z) 
    supposing  \mforall{}a:A.  ((\muparrow{}(succ  a))  {}\mRightarrow{}  (Unit  \msubseteq{}r  B[a]))



Date html generated: 2017_04_14-AM-07_45_01
Last ObjectModification: 2017_02_27-PM-03_15_43

Theory : co-recursion


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