Nuprl Lemma : e-isect_wf
∀[A,B:EType].  (e-isect(A;B) ∈ EType)
Proof
Definitions occuring in Statement : 
e-isect: e-isect(A;B), 
e-type: EType, 
uall: ∀[x:A]. B[x], 
member: t ∈ T
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x], 
member: t ∈ T, 
e-type: EType, 
quotient: x,y:A//B[x; y], 
and: P ∧ Q, 
e-isect: e-isect(A;B), 
so_lambda: λ2x y.t[x; y], 
subtype_rel: A ⊆r B, 
prop: ℙ, 
so_apply: x[s1;s2], 
uimplies: b supposing a, 
all: ∀x:A. B[x], 
implies: P ⇒ Q, 
ext-eq: A ≡ B, 
cand: A c∧ B, 
isect2: T1 ⋂ T2, 
bool: 𝔹, 
unit: Unit, 
it: ⋅, 
btrue: tt, 
ifthenelse: if b then t else f fi , 
bfalse: ff
Lemmas referenced : 
e-type_wf, 
quotient-member-eq, 
ext-eq_wf, 
ext-eq-equiv, 
isect2_wf, 
isect2_decomp, 
bool_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation_alt, 
cut, 
sqequalHypSubstitution, 
pointwiseFunctionalityForEquality, 
introduction, 
extract_by_obid, 
hypothesis, 
sqequalRule, 
pertypeElimination, 
productElimination, 
thin, 
instantiate, 
isectElimination, 
universeEquality, 
lambdaEquality_alt, 
hypothesisEquality, 
applyEquality, 
cumulativity, 
inhabitedIsType, 
equalityTransitivity, 
equalitySymmetry, 
independent_isectElimination, 
dependent_functionElimination, 
independent_functionElimination, 
productIsType, 
equalityIsType4, 
because_Cache, 
universeIsType, 
independent_pairFormation, 
isect_memberEquality, 
unionElimination, 
equalityElimination
Latex:
\mforall{}[A,B:EType].    (e-isect(A;B)  \mmember{}  EType)
Date html generated:
2020_05_20-AM-08_24_32
Last ObjectModification:
2018_10_12-PM-00_32_14
Theory : lattices
Home
Index