Nuprl Lemma : not-l_all-dec

∀[T:Type]. ∀L:T List. ∀P:T ⟶ ℙ.  ((∀x:T. Dec(P[x])) ⇒ (¬(∀x∈L.P[x]) ⇐⇒ (∃x∈L. ¬P[x])))


Proof




Definitions occuring in Statement :  l_exists: (∃x∈L. P[x]),  l_all: (∀x∈L.P[x]),  list: T List,  decidable: Dec(P),  uall: ∀[x:A]. B[x],  prop: ℙ,  so_apply: x[s],  all: ∀x:A. B[x],  iff: P ⇐⇒ Q,  not: ¬A,  implies: P ⇒ Q,  function: x:A ⟶ B[x],  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  implies: P ⇒ Q,  iff: P ⇐⇒ Q,  and: P ∧ Q,  member: t ∈ T,  prop: ℙ,  so_lambda: λ2x.t[x],  so_apply: x[s],  rev_implies: P ⇐ Q,  not: ¬A,  false: False,  decidable: Dec(P),  or: P ∨ Q,  exists: ∃x:A. B[x]
Lemmas referenced :  not_wf,  l_all_wf,  l_member_wf,  l_exists_wf,  all_wf,  decidable_wf,  list_wf,  not-l_exists,  l_all_iff,  decidable__l_exists,  decidable__not,  l_exists_iff
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  lambdaFormation,  independent_pairFormation,  cut,  lemma_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesisEquality,  sqequalRule,  lambdaEquality,  applyEquality,  setElimination,  rename,  setEquality,  hypothesis,  independent_functionElimination,  voidElimination,  functionEquality,  cumulativity,  universeEquality,  because_Cache,  dependent_functionElimination,  productElimination,  unionElimination

Latex:
\mforall{}[T:Type].  \mforall{}L:T  List.  \mforall{}P:T  {}\mrightarrow{}  \mBbbP{}.    ((\mforall{}x:T.  Dec(P[x]))  {}\mRightarrow{}  (\mneg{}(\mforall{}x\mmember{}L.P[x])  \mLeftarrow{}{}\mRightarrow{}  (\mexists{}x\mmember{}L.  \mneg{}P[x])))



Date html generated: 2016_05_14-AM-07_48_07
Last ObjectModification: 2015_12_26-PM-02_55_35

Theory : list_1


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