Nuprl Lemma : W-induction1-extract

∀[A:Type]. ∀[B:A ⟶ Type]. ∀[Q:W(A;a.B[a]) ⟶ ℙ].
  ((∀a:A. ∀f:B[a] ⟶ W(A;a.B[a]).  ((∀b:B[a]. Q[f b]) ⇒ Q[Wsup(a;f)])) ⇒ (∀w:W(A;a.B[a]). Q[w]))


Proof




Definitions occuring in Statement :  Wsup: Wsup(a;b),  W: W(A;a.B[a]),  uall: ∀[x:A]. B[x],  prop: ℙ,  so_apply: x[s],  all: ∀x:A. B[x],  implies: P ⇒ Q,  apply: f a,  function: x:A ⟶ B[x],  universe: Type
Definitions unfolded in proof :  member: t ∈ T,  it: ⋅,  so_lambda: so_lambda(x,y,z.t[x; y; z]),  so_apply: x[s1;s2;s3],  pW-rec: pW-rec,  genrec-ap: genrec-ap,  W-induction1,  param-W-induction
Lemmas referenced :  W-induction1,  param-W-induction
Rules used in proof :  introduction,  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  cut,  instantiate,  extract_by_obid,  hypothesis,  sqequalRule,  thin,  sqequalHypSubstitution,  equalityTransitivity,  equalitySymmetry

Latex:
\mforall{}[A:Type].  \mforall{}[B:A  {}\mrightarrow{}  Type].  \mforall{}[Q:W(A;a.B[a])  {}\mrightarrow{}  \mBbbP{}].
    ((\mforall{}a:A.  \mforall{}f:B[a]  {}\mrightarrow{}  W(A;a.B[a]).    ((\mforall{}b:B[a].  Q[f  b])  {}\mRightarrow{}  Q[Wsup(a;f)]))  {}\mRightarrow{}  (\mforall{}w:W(A;a.B[a]).  Q[w]))



Date html generated: 2018_05_21-PM-00_05_36
Last ObjectModification: 2018_05_19-AM-07_00_36

Theory : co-recursion


Home Index