Nuprl Lemma : presheaf-fun-equal

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


Proof




Definitions occuring in Statement :  presheaf-fun: (A ⟶ B) presheaf-term-at: u(a) presheaf-term: {X ⊢ _:A} presheaf-type-at: A(a) presheaf-type: {X ⊢ _} psc-restriction: f(s) I_set: A(I) ps_context: __⊢ uimplies: supposing a 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] uimplies: supposing a member: t ∈ T subtype_rel: A ⊆B presheaf-term: {X ⊢ _:A} presheaf-fun: (A ⟶ B) all: x:A. B[x] presheaf-fun-family: presheaf-fun-family(C; X; A; B; I; a) squash: T presheaf-term-at: u(a) true: True implies:  Q
Lemmas referenced :  presheaf-term_wf presheaf-fun_wf presheaf-type_wf ps_context_wf small-category-cumulativity-2 small-category_wf presheaf_type_at_pair_lemma presheaf-type-at_wf psc-restriction_wf cat-arrow_wf presheaf-type-ap-morph_wf cat-comp_wf subtype_rel-equal psc-restriction-comp I_set_wf presheaf-term-equal cat-ob_wf presheaf-term-at_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation_alt because_Cache universeIsType cut introduction extract_by_obid sqequalHypSubstitution isectElimination thin hypothesisEquality hypothesis instantiate applyEquality sqequalRule functionExtensionality setElimination rename dependent_functionElimination Error :memTop,  applyLambdaEquality imageMemberEquality baseClosed imageElimination dependent_set_memberEquality_alt functionIsType inhabitedIsType equalityIstype independent_isectElimination lambdaEquality_alt natural_numberEquality equalitySymmetry equalityTransitivity isectIsType lambdaFormation_alt independent_functionElimination

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



Date html generated: 2020_05_20-PM-01_29_41
Last ObjectModification: 2020_04_02-PM-06_26_16

Theory : presheaf!models!of!type!theory


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