Nuprl Lemma : presheaf-term-at-morph

[C:SmallCategory]. ∀[X:ps_context{j:l}(C)]. ∀[A:{X ⊢ _}]. ∀[u:{X ⊢ _:A}]. ∀[I:cat-ob(C)]. ∀[a:X(I)]. ∀[J:cat-ob(C)].
[f:cat-arrow(C) I].
  ((u(a) f) u(f(a)) ∈ A(f(a)))


Proof




Definitions occuring in Statement :  presheaf-term-at: u(a) presheaf-term: {X ⊢ _:A} presheaf-type-ap-morph: (u f) presheaf-type-at: A(a) presheaf-type: {X ⊢ _} psc-restriction: f(s) I_set: A(I) ps_context: __⊢ uall: [x:A]. B[x] apply: a equal: t ∈ T cat-arrow: cat-arrow(C) cat-ob: cat-ob(C) small-category: SmallCategory
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T presheaf-type: {X ⊢ _} presheaf-term: {X ⊢ _:A} all: x:A. B[x] presheaf-term-at: u(a) subtype_rel: A ⊆B
Lemmas referenced :  presheaf_type_at_pair_lemma presheaf_type_ap_morph_pair_lemma cat-arrow_wf I_set_wf cat-ob_wf presheaf-term_wf presheaf-type_wf ps_context_wf small-category-cumulativity-2 small-category_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation_alt introduction cut sqequalHypSubstitution setElimination thin rename productElimination sqequalRule extract_by_obid dependent_functionElimination Error :memTop,  hypothesis hypothesisEquality universeIsType applyEquality isectElimination isect_memberEquality_alt axiomEquality isectIsTypeImplies inhabitedIsType instantiate

Latex:
\mforall{}[C:SmallCategory].  \mforall{}[X:ps\_context\{j:l\}(C)].  \mforall{}[A:\{X  \mvdash{}  \_\}].  \mforall{}[u:\{X  \mvdash{}  \_:A\}].  \mforall{}[I:cat-ob(C)].
\mforall{}[a:X(I)].  \mforall{}[J:cat-ob(C)].  \mforall{}[f:cat-arrow(C)  J  I].
    ((u(a)  a  f)  =  u(f(a)))



Date html generated: 2020_05_20-PM-01_26_41
Last ObjectModification: 2020_04_01-PM-01_51_05

Theory : presheaf!models!of!type!theory


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