Nuprl Lemma : nil_member!
∀[T:Type]. ∀x:T. ((x ∈! []) 
⇐⇒ False)
Proof
Definitions occuring in Statement : 
l_member!: (x ∈! l)
, 
nil: []
, 
uall: ∀[x:A]. B[x]
, 
all: ∀x:A. B[x]
, 
iff: P 
⇐⇒ Q
, 
false: False
, 
universe: Type
Definitions unfolded in proof : 
l_member!: (x ∈! l)
, 
uall: ∀[x:A]. B[x]
, 
all: ∀x:A. B[x]
, 
iff: P 
⇐⇒ Q
, 
and: P ∧ Q
, 
implies: P 
⇒ Q
, 
false: False
, 
select: L[n]
, 
member: t ∈ T
, 
uimplies: b supposing a
, 
nil: []
, 
it: ⋅
, 
so_lambda: λ2x y.t[x; y]
, 
top: Top
, 
so_apply: x[s1;s2]
, 
exists: ∃x:A. B[x]
, 
cand: A c∧ B
, 
nat: ℕ
, 
ge: i ≥ j 
, 
satisfiable_int_formula: satisfiable_int_formula(fmla)
, 
not: ¬A
, 
prop: ℙ
, 
so_lambda: λ2x.t[x]
, 
decidable: Dec(P)
, 
or: P ∨ Q
, 
so_apply: x[s]
, 
rev_implies: P 
⇐ Q
Lemmas referenced : 
length_of_nil_lemma, 
stuck-spread, 
base_wf, 
nat_properties, 
satisfiable-full-omega-tt, 
intformand_wf, 
intformless_wf, 
itermVar_wf, 
itermConstant_wf, 
intformle_wf, 
int_formula_prop_and_lemma, 
int_formula_prop_less_lemma, 
int_term_value_var_lemma, 
int_term_value_constant_lemma, 
int_formula_prop_le_lemma, 
int_formula_prop_wf, 
exists_wf, 
nat_wf, 
less_than_wf, 
length_wf, 
nil_wf, 
equal_wf, 
select_wf, 
decidable__le, 
intformnot_wf, 
int_formula_prop_not_lemma, 
all_wf, 
false_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalRule, 
sqequalReflexivity, 
sqequalTransitivity, 
computationStep, 
isect_memberFormation, 
lambdaFormation, 
independent_pairFormation, 
cut, 
sqequalHypSubstitution, 
introduction, 
extract_by_obid, 
hypothesis, 
isectElimination, 
thin, 
baseClosed, 
independent_isectElimination, 
isect_memberEquality, 
voidElimination, 
voidEquality, 
productElimination, 
hypothesisEquality, 
setElimination, 
rename, 
natural_numberEquality, 
dependent_pairFormation, 
lambdaEquality, 
int_eqEquality, 
intEquality, 
dependent_functionElimination, 
computeAll, 
productEquality, 
because_Cache, 
cumulativity, 
unionElimination, 
functionEquality, 
universeEquality
Latex:
\mforall{}[T:Type].  \mforall{}x:T.  ((x  \mmember{}!  [])  \mLeftarrow{}{}\mRightarrow{}  False)
Date html generated:
2017_04_17-AM-07_27_35
Last ObjectModification:
2017_02_27-PM-04_05_52
Theory : list_1
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