Nuprl Lemma : presheaf-snd-pair

[C:SmallCategory]. ∀[X:ps_context{j:l}(C)]. ∀[A:{X ⊢ _}]. ∀[B:{X.A ⊢ _}]. ∀[u:{X ⊢ _:A}]. ∀[v:{X ⊢ _:(B)[u]}].
  (presheaf-pair(u;v).2 v ∈ {X ⊢ _:(B)[u]})


Proof




Definitions occuring in Statement :  presheaf-pair: presheaf-pair(u;v) presheaf-snd: p.2 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] equal: t ∈ T small-category: SmallCategory
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T uimplies: supposing a subtype_rel: A ⊆B presheaf-term: {X ⊢ _:A} presheaf-pair: presheaf-pair(u;v) presheaf-snd: p.2 pi2: snd(t)
Lemmas referenced :  presheaf-term-equal presheaf-term_wf pscm-ap-type_wf psc-adjoin_wf small-category-cumulativity-2 ps_context_cumulativity2 presheaf-type-cumulativity2 pscm-id-adjoin_wf presheaf-type_wf ps_context_wf small-category_wf I_set_wf cat-ob_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation_alt introduction cut equalitySymmetry extract_by_obid sqequalHypSubstitution isectElimination thin hypothesisEquality independent_isectElimination hypothesis universeIsType instantiate applyEquality sqequalRule because_Cache isect_memberEquality_alt axiomEquality isectIsTypeImplies inhabitedIsType setElimination rename lambdaEquality_alt functionExtensionality

Latex:
\mforall{}[C:SmallCategory].  \mforall{}[X:ps\_context\{j:l\}(C)].  \mforall{}[A:\{X  \mvdash{}  \_\}].  \mforall{}[B:\{X.A  \mvdash{}  \_\}].  \mforall{}[u:\{X  \mvdash{}  \_:A\}].
\mforall{}[v:\{X  \mvdash{}  \_:(B)[u]\}].
    (presheaf-pair(u;v).2  =  v)



Date html generated: 2020_05_20-PM-01_33_26
Last ObjectModification: 2020_04_02-PM-06_31_16

Theory : presheaf!models!of!type!theory


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