Nuprl Lemma : singleton-center_wf
∀[X:j⊢]. ∀[A:{X ⊢ _}]. ∀[a:{X ⊢ _:A}].  (singleton-center(X;a) ∈ {X ⊢ _:Singleton(a)})
Proof
Definitions occuring in Statement : 
singleton-center: singleton-center(X;a)
, 
singleton-type: Singleton(a)
, 
cubical-term: {X ⊢ _:A}
, 
cubical-type: {X ⊢ _}
, 
cubical_set: CubicalSet
, 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
singleton-type: Singleton(a)
, 
singleton-center: singleton-center(X;a)
, 
subtype_rel: A ⊆r B
, 
uimplies: b supposing a
Lemmas referenced : 
cubical-pair_wf, 
path-type_wf, 
cube-context-adjoin_wf, 
cubical_set_cumulativity-i-j, 
cubical-type-cumulativity2, 
csm-ap-type_wf, 
cc-fst_wf, 
csm-ap-term_wf, 
cc-snd_wf, 
cubical-refl_wf, 
subset-cubical-term2, 
sub_cubical_set_self, 
csm-id-adjoin_wf, 
path-type-q-id-adjoin, 
cubical-term_wf, 
cubical-type_wf, 
cubical_set_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation_alt, 
introduction, 
cut, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
hypothesisEquality, 
instantiate, 
applyEquality, 
hypothesis, 
sqequalRule, 
because_Cache, 
equalityTransitivity, 
equalitySymmetry, 
independent_isectElimination, 
axiomEquality, 
universeIsType, 
isect_memberEquality_alt, 
isectIsTypeImplies, 
inhabitedIsType
Latex:
\mforall{}[X:j\mvdash{}].  \mforall{}[A:\{X  \mvdash{}  \_\}].  \mforall{}[a:\{X  \mvdash{}  \_:A\}].    (singleton-center(X;a)  \mmember{}  \{X  \mvdash{}  \_:Singleton(a)\})
Date html generated:
2020_05_20-PM-03_29_25
Last ObjectModification:
2020_04_06-PM-06_51_19
Theory : cubical!type!theory
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