Nuprl Lemma : power-set-lift-well-founded-implies

∀[T:Type]. ∀[R:T ⟶ T ⟶ ℙ].
  ((∀x:T. (R x x))
  ⇒ (∀f:ℕ ⟶ P(T). (↓∃n:ℕ. ((power-set-lift(T;R) (f (n + 1)) (f n)) ⇒ (power-set-lift(T;R) (f n) (f (n + 1))))))
  ⇒ AFx,y:T.R[x;y])


Proof




Definitions occuring in Statement :  power-set-lift: power-set-lift(T;R),  power-set: P(T),  almost-full: AFx,y:T.R[x; y],  nat: ℕ,  uall: ∀[x:A]. B[x],  prop: ℙ,  so_apply: x[s1;s2],  all: ∀x:A. B[x],  exists: ∃x:A. B[x],  squash: ↓T,  implies: P ⇒ Q,  apply: f a,  function: x:A ⟶ B[x],  add: n + m,  natural_number: $n,  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  implies: P ⇒ Q,  almost-full: AFx,y:T.R[x; y],  all: ∀x:A. B[x],  prop: ℙ,  subtype_rel: A ⊆r B,  so_lambda: λ2x.t[x],  nat: ℕ,  decidable: Dec(P),  or: P ∨ Q,  iff: P ⇐⇒ Q,  and: P ∧ Q,  not: ¬A,  rev_implies: P ⇐ Q,  false: False,  uiff: uiff(P;Q),  uimplies: b supposing a,  sq_stable: SqStable(P),  squash: ↓T,  subtract: n - m,  top: Top,  le: A ≤ B,  less_than': less_than'(a;b),  true: True,  so_apply: x[s],  exists: ∃x:A. B[x],  power-set: P(T),  power-set-lift: power-set-lift(T;R),  set-member: (x ∈ s),  cand: A c∧ B,  guard: {T},  int_upper: {i...},  so_apply: x[s1;s2]
Lemmas referenced :  iff_weakening_equal,  less_than_wf,  not-lt-2,  decidable__lt,  int_subtype_base,  add-is-int-iff,  le_reflexive,  and_wf,  equal_wf,  le-add-cancel2,  zero-mul,  add-mul-special,  int_upper_subtype_int_upper,  int_upper_subtype_nat,  subtype_rel_dep_function,  int_upper_wf,  le_wf,  le-add-cancel,  add-zero,  add_functionality_wrt_le,  add-commutes,  add-swap,  add-associates,  minus-one-mul-top,  zero-add,  minus-one-mul,  minus-add,  condition-implies-le,  sq_stable__le,  not-le-2,  false_wf,  decidable__le,  power-set-lift_wf,  exists_wf,  squash_wf,  power-set_wf,  all_wf,  nat_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  lambdaFormation,  functionEquality,  lemma_by_obid,  hypothesis,  hypothesisEquality,  thin,  instantiate,  sqequalHypSubstitution,  isectElimination,  applyEquality,  lambdaEquality,  cumulativity,  universeEquality,  sqequalRule,  dependent_set_memberEquality,  addEquality,  setElimination,  rename,  natural_numberEquality,  dependent_functionElimination,  unionElimination,  independent_pairFormation,  voidElimination,  productElimination,  independent_functionElimination,  independent_isectElimination,  imageMemberEquality,  baseClosed,  imageElimination,  isect_memberEquality,  voidEquality,  intEquality,  because_Cache,  minusEquality,  dependent_pairEquality,  dependent_pairFormation,  multiplyEquality,  baseApply,  closedConclusion,  productEquality,  equalityTransitivity,  equalitySymmetry

Latex:
\mforall{}[T:Type].  \mforall{}[R:T  {}\mrightarrow{}  T  {}\mrightarrow{}  \mBbbP{}].
    ((\mforall{}x:T.  (R  x  x))
    {}\mRightarrow{}  (\mforall{}f:\mBbbN{}  {}\mrightarrow{}  P(T)
                (\mdownarrow{}\mexists{}n:\mBbbN{}
                      ((power-set-lift(T;R)  (f  (n  +  1))  (f  n))  {}\mRightarrow{}  (power-set-lift(T;R)  (f  n)  (f  (n  +  1))))))
    {}\mRightarrow{}  AFx,y:T.R[x;y])



Date html generated: 2016_05_13-PM-03_51_45
Last ObjectModification: 2016_01_14-PM-07_00_34

Theory : bar-induction


Home Index