Nuprl Lemma : presheaf-apply_wf
∀[C:SmallCategory]. ∀[X:ps_context{j:l}(C)]. ∀[A:{X ⊢ _}]. ∀[B:{X.A ⊢ _}]. ∀[w:{X ⊢ _:ΠA B}]. ∀[u:{X ⊢ _:A}].
  (presheaf-apply(w;u) ∈ {X ⊢ _:(B)[u]})
Proof
Definitions occuring in Statement : 
presheaf-apply: presheaf-apply(w;u)
, 
presheaf-pi: ΠA B
, 
pscm-id-adjoin: [u]
, 
psc-adjoin: X.A
, 
presheaf-term: {X ⊢ _:A}
, 
pscm-ap-type: (AF)s
, 
presheaf-type: {X ⊢ _}
, 
ps_context: __⊢
, 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
small-category: SmallCategory
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
presheaf-apply: presheaf-apply(w;u)
, 
subtype_rel: A ⊆r B
Lemmas referenced : 
presheaf-app_wf, 
ps_context_cumulativity2, 
presheaf-type-cumulativity2, 
psc-adjoin_wf, 
presheaf-term_wf, 
presheaf-pi_wf, 
presheaf-type_wf, 
small-category-cumulativity-2, 
ps_context_wf, 
small-category_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation_alt, 
introduction, 
cut, 
sqequalRule, 
thin, 
instantiate, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
hypothesisEquality, 
applyEquality, 
because_Cache, 
hypothesis, 
axiomEquality, 
equalityTransitivity, 
equalitySymmetry, 
universeIsType, 
isect_memberEquality_alt, 
isectIsTypeImplies, 
inhabitedIsType
Latex:
\mforall{}[C:SmallCategory].  \mforall{}[X:ps\_context\{j:l\}(C)].  \mforall{}[A:\{X  \mvdash{}  \_\}].  \mforall{}[B:\{X.A  \mvdash{}  \_\}].  \mforall{}[w:\{X  \mvdash{}  \_:\mPi{}A  B\}].
\mforall{}[u:\{X  \mvdash{}  \_:A\}].
    (presheaf-apply(w;u)  \mmember{}  \{X  \mvdash{}  \_:(B)[u]\})
Date html generated:
2020_05_20-PM-01_31_13
Last ObjectModification:
2020_04_02-PM-03_02_38
Theory : presheaf!models!of!type!theory
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