Nuprl Lemma : decidable-exists-finite
∀[T:Type]. ∀[P:T ─→ ℙ].  ((∀x:T. Dec(P[x])) 
⇒ finite-type(T) 
⇒ Dec(∃x:T. P[x]))
Proof
Definitions occuring in Statement : 
finite-type: finite-type(T)
, 
decidable: Dec(P)
, 
uall: ∀[x:A]. B[x]
, 
prop: ℙ
, 
so_apply: x[s]
, 
all: ∀x:A. B[x]
, 
exists: ∃x:A. B[x]
, 
implies: P 
⇒ Q
, 
function: x:A ─→ B[x]
, 
universe: Type
Lemmas : 
finite-type_wf, 
all_wf, 
decidable_wf, 
exists_wf, 
int_seg_wf, 
iff_weakening_equal, 
decidable_functionality, 
decidable__exists_int_seg
\mforall{}[T:Type].  \mforall{}[P:T  {}\mrightarrow{}  \mBbbP{}].    ((\mforall{}x:T.  Dec(P[x]))  {}\mRightarrow{}  finite-type(T)  {}\mRightarrow{}  Dec(\mexists{}x:T.  P[x]))
Date html generated:
2015_07_17-AM-09_05_09
Last ObjectModification:
2015_02_04-PM-06_27_35
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