Nuprl Lemma : l_exists_nil
∀[P:Top]. ((∃x∈[]. P[x]) ⇐⇒ False)
Proof
Definitions occuring in Statement : 
l_exists: (∃x∈L. P[x]), 
nil: [], 
uall: ∀[x:A]. B[x], 
top: Top, 
so_apply: x[s], 
iff: P ⇐⇒ Q, 
false: False
Definitions unfolded in proof : 
l_exists: (∃x∈L. P[x]), 
select: L[n], 
uall: ∀[x:A]. B[x], 
member: t ∈ T, 
uimplies: b supposing a, 
all: ∀x:A. B[x], 
nil: [], 
it: ⋅, 
so_lambda: λ2x y.t[x; y], 
top: Top, 
so_apply: x[s1;s2], 
iff: P ⇐⇒ Q, 
and: P ∧ Q, 
implies: P ⇒ Q, 
false: False, 
exists: ∃x:A. B[x], 
int_seg: {i..j-}, 
lelt: i ≤ j < k, 
guard: {T}, 
prop: ℙ, 
so_lambda: λ2x.t[x], 
so_apply: x[s], 
rev_implies: P ⇐ Q
Lemmas referenced : 
top_wf, 
false_wf, 
int_seg_wf, 
exists_wf, 
less_than_irreflexivity, 
less_than_transitivity1, 
base_wf, 
stuck-spread, 
length_of_nil_lemma
Rules used in proof : 
sqequalSubstitution, 
sqequalRule, 
sqequalReflexivity, 
sqequalTransitivity, 
computationStep, 
cut, 
lemma_by_obid, 
hypothesis, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
baseClosed, 
independent_isectElimination, 
lambdaFormation, 
isect_memberEquality, 
voidElimination, 
voidEquality, 
isect_memberFormation, 
independent_pairFormation, 
productElimination, 
setElimination, 
rename, 
hypothesisEquality, 
natural_numberEquality, 
independent_functionElimination, 
because_Cache, 
lambdaEquality
Latex:
\mforall{}[P:Top].  ((\mexists{}x\mmember{}[].  P[x])  \mLeftarrow{}{}\mRightarrow{}  False)
Date html generated:
2016_05_14-AM-06_40_22
Last ObjectModification:
2016_01_06-PM-08_33_59
Theory : list_0
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