Nuprl Lemma : not-not-finite-xmiddle
∀[T:Type]. (finite(T) 
⇒ (∀P:T ⟶ ℙ. (¬¬(∀i:T. (P[i] ∨ (¬P[i]))))))
Proof
Definitions occuring in Statement : 
finite: finite(T)
, 
uall: ∀[x:A]. B[x]
, 
prop: ℙ
, 
so_apply: x[s]
, 
all: ∀x:A. B[x]
, 
not: ¬A
, 
implies: P 
⇒ Q
, 
or: P ∨ Q
, 
function: x:A ⟶ B[x]
, 
universe: Type
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
implies: P 
⇒ Q
, 
finite: finite(T)
, 
exists: ∃x:A. B[x]
, 
nat: ℕ
, 
prop: ℙ
, 
equipollent: A ~ B
, 
biject: Bij(A;B;f)
, 
and: P ∧ Q
Lemmas referenced : 
not-not-finite-xmiddle-1, 
int_seg_wf, 
surject_wf, 
finite_wf, 
istype-universe, 
equipollent_inversion
Rules used in proof : 
cut, 
introduction, 
extract_by_obid, 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation_alt, 
hypothesis, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
hypothesisEquality, 
lambdaFormation_alt, 
independent_functionElimination, 
productElimination, 
dependent_pairFormation_alt, 
sqequalRule, 
productIsType, 
functionIsType, 
universeIsType, 
natural_numberEquality, 
setElimination, 
rename, 
because_Cache, 
instantiate, 
universeEquality
Latex:
\mforall{}[T:Type].  (finite(T)  {}\mRightarrow{}  (\mforall{}P:T  {}\mrightarrow{}  \mBbbP{}.  (\mneg{}\mneg{}(\mforall{}i:T.  (P[i]  \mvee{}  (\mneg{}P[i]))))))
Date html generated:
2020_05_19-PM-10_00_48
Last ObjectModification:
2019_10_24-AM-10_45_45
Theory : equipollence!!cardinality!
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