Nuprl Lemma : fpf-sub-val

∀[A:Type]. ∀[B:A ⟶ Type].
  ∀eq:EqDecider(A). ∀f,g:a:A fp-> B[a]. ∀x:A.
    ∀[P:a:A ⟶ B[a] ⟶ ℙ]. z != f(x) ==> P[x;z] ⇒ z != g(x) ==> P[x;z] supposing g ⊆ f


Proof




Definitions occuring in Statement :  fpf-sub: f ⊆ g,  fpf-val: z != f(x) ==> P[a; z],  fpf: a:A fp-> B[a],  deq: EqDecider(T),  uimplies: b supposing a,  uall: ∀[x:A]. B[x],  prop: ℙ,  so_apply: x[s1;s2],  so_apply: x[s],  all: ∀x:A. B[x],  implies: P ⇒ Q,  function: x:A ⟶ B[x],  universe: Type
Definitions unfolded in proof :  fpf-val: z != f(x) ==> P[a; z],  fpf-sub: f ⊆ g,  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  uimplies: b supposing a,  member: t ∈ T,  implies: P ⇒ Q,  cand: A c∧ B,  subtype_rel: A ⊆r B,  so_lambda: λ2x.t[x],  so_apply: x[s],  top: Top,  prop: ℙ,  so_apply: x[s1;s2]
Lemmas referenced :  assert_witness,  fpf-dom_wf,  subtype-fpf2,  top_wf,  assert_wf,  fpf-ap_wf,  all_wf,  equal_wf,  fpf_wf,  deq_wf
Rules used in proof :  sqequalSubstitution,  sqequalRule,  sqequalReflexivity,  sqequalTransitivity,  computationStep,  isect_memberFormation,  lambdaFormation,  cut,  introduction,  sqequalHypSubstitution,  lambdaEquality,  dependent_functionElimination,  thin,  hypothesisEquality,  productElimination,  independent_pairEquality,  extract_by_obid,  isectElimination,  cumulativity,  applyEquality,  functionExtensionality,  hypothesis,  independent_isectElimination,  isect_memberEquality,  voidElimination,  voidEquality,  because_Cache,  independent_functionElimination,  axiomEquality,  rename,  functionEquality,  productEquality,  universeEquality,  hyp_replacement,  equalitySymmetry,  applyLambdaEquality

Latex:
\mforall{}[A:Type].  \mforall{}[B:A  {}\mrightarrow{}  Type].
    \mforall{}eq:EqDecider(A).  \mforall{}f,g:a:A  fp->  B[a].  \mforall{}x:A.
        \mforall{}[P:a:A  {}\mrightarrow{}  B[a]  {}\mrightarrow{}  \mBbbP{}].  z  !=  f(x)  ==>  P[x;z]  {}\mRightarrow{}  z  !=  g(x)  ==>  P[x;z]  supposing  g  \msubseteq{}  f



Date html generated: 2018_05_21-PM-09_23_57
Last ObjectModification: 2018_02_09-AM-10_19_29

Theory : finite!partial!functions


Home Index