Nuprl Lemma : bag-from-member-function
∀[T:Type]
  ∀bs:bag(T). ∀P,Q:T ⟶ ℙ.
    ((∀i:T. Dec(Q[i]))
    ⇒ (∀i:T. (i ↓∈ bs ⇒ Q[i] ⇒ P[i]))
    ⇒ (∃b:bag(T). ((∀i:T. (i ↓∈ bs ⇒ Q[i] ⇒ i ↓∈ b)) ∧ (∀i:T. (i ↓∈ b ⇒ P[i])))))
Proof
Definitions occuring in Statement : 
bag-member: x ↓∈ bs, 
bag: bag(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, 
and: P ∧ Q, 
function: x:A ⟶ B[x], 
universe: Type
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x], 
all: ∀x:A. B[x], 
implies: P ⇒ Q, 
exists: ∃x:A. B[x], 
member: t ∈ T, 
so_lambda: λ2x.t[x], 
subtype_rel: A ⊆r B, 
decidable: Dec(P), 
or: P ∨ Q, 
decision: Decision, 
so_apply: x[s], 
prop: ℙ, 
uimplies: b supposing a, 
top: Top, 
and: P ∧ Q, 
cand: A c∧ B, 
uiff: uiff(P;Q), 
rev_uimplies: rev_uimplies(P;Q), 
guard: {T}, 
iff: P ⇐⇒ Q, 
rev_implies: P ⇐ Q, 
bag-member: x ↓∈ bs, 
squash: ↓T
Lemmas referenced : 
bag_wf, 
decidable_wf, 
all_wf, 
and_wf, 
bag-member_wf, 
dec2bool_decidable, 
bag-member-filter, 
assert_wf, 
subtype_rel_bag, 
top_wf, 
not_wf, 
subtype_rel_union, 
dec2bool_wf, 
bag-filter_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
lambdaFormation, 
rename, 
dependent_pairFormation, 
cut, 
lemma_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
cumulativity, 
hypothesisEquality, 
sqequalRule, 
lambdaEquality, 
applyEquality, 
hypothesis, 
universeEquality, 
because_Cache, 
independent_isectElimination, 
isect_memberEquality, 
voidElimination, 
voidEquality, 
setEquality, 
setElimination, 
introduction, 
productElimination, 
independent_pairFormation, 
dependent_functionElimination, 
independent_functionElimination, 
imageElimination, 
imageMemberEquality, 
baseClosed, 
functionEquality
Latex:
\mforall{}[T:Type]
    \mforall{}bs:bag(T).  \mforall{}P,Q:T  {}\mrightarrow{}  \mBbbP{}.
        ((\mforall{}i:T.  Dec(Q[i]))
        {}\mRightarrow{}  (\mforall{}i:T.  (i  \mdownarrow{}\mmember{}  bs  {}\mRightarrow{}  Q[i]  {}\mRightarrow{}  P[i]))
        {}\mRightarrow{}  (\mexists{}b:bag(T).  ((\mforall{}i:T.  (i  \mdownarrow{}\mmember{}  bs  {}\mRightarrow{}  Q[i]  {}\mRightarrow{}  i  \mdownarrow{}\mmember{}  b))  \mwedge{}  (\mforall{}i:T.  (i  \mdownarrow{}\mmember{}  b  {}\mRightarrow{}  P[i])))))
Date html generated:
2016_05_15-PM-02_58_51
Last ObjectModification:
2016_01_16-AM-08_37_36
Theory : bags
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