Nuprl Lemma : l_all_not
∀[T:Type]. ∀L:T List. ∀P:T ⟶ ℙ.  ((∀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
, 
uall: ∀[x:A]. B[x]
, 
prop: ℙ
, 
so_apply: x[s]
, 
all: ∀x:A. B[x]
, 
iff: P 
⇐⇒ Q
, 
not: ¬A
, 
function: x:A ⟶ B[x]
, 
universe: Type
Definitions unfolded in proof : 
l_exists: (∃x∈L. P[x])
, 
l_all: (∀x∈L.P[x])
, 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
all: ∀x:A. B[x]
, 
iff: P 
⇐⇒ Q
, 
and: P ∧ Q
, 
implies: P 
⇒ Q
, 
not: ¬A
, 
false: False
, 
exists: ∃x:A. B[x]
, 
prop: ℙ
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
, 
int_seg: {i..j-}
, 
uimplies: b supposing a
, 
sq_stable: SqStable(P)
, 
lelt: i ≤ j < k
, 
squash: ↓T
, 
rev_implies: P 
⇐ Q
, 
subtype_rel: A ⊆r B
, 
guard: {T}
Lemmas referenced : 
list_wf, 
not_wf, 
all_wf, 
sq_stable__le, 
select_wf, 
length_wf, 
int_seg_wf, 
exists_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalRule, 
sqequalReflexivity, 
sqequalTransitivity, 
computationStep, 
isect_memberFormation, 
introduction, 
cut, 
lambdaFormation, 
independent_pairFormation, 
thin, 
sqequalHypSubstitution, 
productElimination, 
because_Cache, 
hypothesis, 
independent_functionElimination, 
voidElimination, 
lemma_by_obid, 
isectElimination, 
natural_numberEquality, 
cumulativity, 
hypothesisEquality, 
lambdaEquality, 
applyEquality, 
setElimination, 
rename, 
independent_isectElimination, 
imageMemberEquality, 
baseClosed, 
imageElimination, 
dependent_pairFormation, 
functionEquality, 
universeEquality, 
dependent_functionElimination, 
independent_pairEquality
Latex:
\mforall{}[T:Type].  \mforall{}L:T  List.  \mforall{}P:T  {}\mrightarrow{}  \mBbbP{}.    ((\mforall{}x\mmember{}L.\mneg{}P[x])  \mLeftarrow{}{}\mRightarrow{}  \mneg{}(\mexists{}x\mmember{}L.  P[x]))
Date html generated:
2016_05_14-AM-06_40_31
Last ObjectModification:
2016_01_14-PM-08_20_36
Theory : list_0
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