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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