Nuprl Lemma : bag-member-empty-weak
∀[T:Type]. ∀[x:T].  (x ↓∈ {} 
⇐⇒ False)
Proof
Definitions occuring in Statement : 
bag-member: x ↓∈ bs
, 
empty-bag: {}
, 
uall: ∀[x:A]. B[x]
, 
iff: P 
⇐⇒ Q
, 
false: False
, 
universe: Type
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
iff: P 
⇐⇒ Q
, 
and: P ∧ Q
, 
implies: P 
⇒ Q
, 
false: False
, 
uimplies: b supposing a
, 
prop: ℙ
, 
rev_implies: P 
⇐ Q
, 
bag-member: x ↓∈ bs
, 
squash: ↓T
Lemmas referenced : 
false_wf, 
empty-bag_wf, 
bag-member_wf, 
bag-member-empty
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
introduction, 
cut, 
independent_pairFormation, 
lambdaFormation, 
lemma_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
because_Cache, 
hypothesisEquality, 
independent_isectElimination, 
hypothesis, 
voidElimination, 
sqequalRule, 
productElimination, 
independent_pairEquality, 
lambdaEquality, 
dependent_functionElimination, 
imageElimination, 
imageMemberEquality, 
baseClosed, 
isect_memberEquality, 
universeEquality
Latex:
\mforall{}[T:Type].  \mforall{}[x:T].    (x  \mdownarrow{}\mmember{}  \{\}  \mLeftarrow{}{}\mRightarrow{}  False)
Date html generated:
2016_05_15-PM-02_36_56
Last ObjectModification:
2016_01_16-AM-08_50_15
Theory : bags
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