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

[T:Type]. ∀[R:T ⟶ T ⟶ ℙ].
  ((∀x:T. (R 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: uall: [x:A]. B[x] prop: so_apply: x[s1;s2] all: x:A. B[x] exists: x:A. B[x] squash: T implies:  Q apply: a function: x:A ⟶ B[x] add: m natural_number: $n universe: Type
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T implies:  Q almost-full: AFx,y:T.R[x; y] all: x:A. B[x] prop: subtype_rel: A ⊆B so_lambda: λ2x.t[x] nat: decidable: Dec(P) or: P ∨ Q iff: ⇐⇒ Q and: P ∧ Q not: ¬A rev_implies:  Q false: False uiff: uiff(P;Q) uimplies: supposing a sq_stable: SqStable(P) squash: T subtract: 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: 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