Nuprl Lemma : bnot_thru_exists
∀A:Type. ∀as:A List. ∀f:A ⟶ 𝔹.  ¬b(∃bx(:A) ∈ as. f[x]) = ∀bx(:A) ∈ as. (¬bf[x])
Proof
Definitions occuring in Statement : 
bexists: bexists, 
ball: ball, 
list: T List, 
bnot: ¬bb, 
bool: 𝔹, 
so_apply: x[s], 
all: ∀x:A. B[x], 
function: x:A ⟶ B[x], 
universe: Type, 
equal: s = t ∈ T
Definitions unfolded in proof : 
all: ∀x:A. B[x], 
uall: ∀[x:A]. B[x], 
member: t ∈ T, 
so_lambda: λ2x.t[x], 
so_apply: x[s], 
implies: P ⇒ Q, 
top: Top, 
bnot: ¬bb, 
ifthenelse: if b then t else f fi , 
bfalse: ff, 
squash: ↓T, 
prop: ℙ, 
true: True, 
bool: 𝔹, 
unit: Unit, 
it: ⋅, 
btrue: tt, 
band: p ∧b q, 
uiff: uiff(P;Q), 
and: P ∧ Q, 
uimplies: b supposing a, 
exists: ∃x:A. B[x], 
or: P ∨ Q, 
sq_type: SQType(T), 
guard: {T}, 
assert: ↑b, 
false: False, 
subtype_rel: A ⊆r B, 
iff: P ⇐⇒ Q, 
rev_implies: P ⇐ Q
Lemmas referenced : 
list_induction, 
all_wf, 
bool_wf, 
equal_wf, 
bnot_wf, 
bexists_wf, 
ball_wf, 
list_wf, 
bexists_nil_lemma, 
ball_nil_lemma, 
btrue_wf, 
bexists_cons_lemma, 
ball_cons_lemma, 
bnot_thru_bor, 
squash_wf, 
true_wf, 
band_wf, 
eqtt_to_assert, 
bool_cases_sqequal, 
subtype_base_sq, 
bool_subtype_base, 
eqff_to_assert, 
assert-bnot, 
iff_weakening_equal
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
lambdaFormation, 
cut, 
thin, 
introduction, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
hypothesisEquality, 
sqequalRule, 
lambdaEquality, 
functionEquality, 
cumulativity, 
hypothesis, 
dependent_functionElimination, 
applyEquality, 
functionExtensionality, 
independent_functionElimination, 
isect_memberEquality, 
voidElimination, 
voidEquality, 
rename, 
imageElimination, 
because_Cache, 
equalityTransitivity, 
equalitySymmetry, 
natural_numberEquality, 
imageMemberEquality, 
baseClosed, 
unionElimination, 
equalityElimination, 
productElimination, 
independent_isectElimination, 
dependent_pairFormation, 
promote_hyp, 
instantiate, 
universeEquality
Latex:
\mforall{}A:Type.  \mforall{}as:A  List.  \mforall{}f:A  {}\mrightarrow{}  \mBbbB{}.    \mneg{}\msubb{}(\mexists{}\msubb{}x(:A)  \mmember{}  as.  f[x])  =  \mforall{}\msubb{}x(:A)  \mmember{}  as.  (\mneg{}\msubb{}f[x])
Date html generated:
2017_10_01-AM-09_56_00
Last ObjectModification:
2017_03_03-PM-00_56_08
Theory : list_2
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