Nuprl Lemma : classical-exists1

∀[T:Type]. ∀[P:T ⟶ ℙ].  ((∃x:T. {P[x]}) ⇒ {∃x:T. P[x]})


Proof




Definitions occuring in Statement :  classical: {P},  uall: ∀[x:A]. B[x],  prop: ℙ,  so_apply: x[s],  exists: ∃x:A. B[x],  implies: P ⇒ Q,  function: x:A ⟶ B[x],  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  implies: P ⇒ Q,  exists: ∃x:A. B[x],  prop: ℙ,  so_lambda: λ2x.t[x],  so_apply: x[s],  classical: {P},  unit: Unit
Lemmas referenced :  it_wf,  classical_wf,  exists_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  lambdaFormation,  sqequalHypSubstitution,  productElimination,  thin,  lemma_by_obid,  isectElimination,  hypothesisEquality,  sqequalRule,  lambdaEquality,  applyEquality,  hypothesis,  dependent_functionElimination,  setElimination,  rename,  dependent_set_memberEquality,  axiomEquality,  natural_numberEquality,  functionEquality,  cumulativity,  universeEquality,  isect_memberEquality,  because_Cache,  dependent_pairFormation

Latex:
\mforall{}[T:Type].  \mforall{}[P:T  {}\mrightarrow{}  \mBbbP{}].    ((\mexists{}x:T.  \{P[x]\})  {}\mRightarrow{}  \{\mexists{}x:T.  P[x]\})



Date html generated: 2016_05_13-PM-03_16_56
Last ObjectModification: 2016_01_06-PM-05_20_41

Theory : core_2


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