Nuprl Lemma : presheaf-type-ap-morph-comp-eq

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


Proof




Definitions occuring in Statement :  presheaf-type-ap-morph: (u a f),  presheaf-type-at: A(a),  presheaf-type: {X ⊢ _},  psc-restriction: f(s),  I_set: A(I),  ps_context: __⊢,  uimplies: b supposing a,  uall: ∀[x:A]. B[x],  apply: f a,  equal: s = t ∈ T,  cat-comp: cat-comp(C),  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,  uimplies: b supposing a,  subtype_rel: A ⊆r B,  and: P ∧ Q,  prop: ℙ,  squash: ↓T,  true: True,  all: ∀x:A. B[x]
Lemmas referenced :  psc-restriction_wf,  ps_context_cumulativity2,  small-category-cumulativity-2,  presheaf-type-at_wf,  I_set_wf,  cat-arrow_wf,  presheaf-type-ap-morph-comp,  equal_wf,  cat-comp_wf,  presheaf-type-ap-morph_wf,  subtype_rel-equal,  psc-restriction-comp
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation_alt,  introduction,  cut,  hypothesis,  equalityIstype,  inhabitedIsType,  hypothesisEquality,  thin,  instantiate,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  applyEquality,  because_Cache,  sqequalRule,  isect_memberEquality_alt,  axiomEquality,  isectIsTypeImplies,  universeIsType,  dependent_set_memberEquality_alt,  independent_pairFormation,  equalityTransitivity,  equalitySymmetry,  productIsType,  hyp_replacement,  applyLambdaEquality,  setElimination,  rename,  productElimination,  lambdaEquality_alt,  imageElimination,  natural_numberEquality,  imageMemberEquality,  baseClosed,  independent_isectElimination,  dependent_functionElimination

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



Date html generated: 2020_05_20-PM-01_26_01
Last ObjectModification: 2020_04_01-PM-00_01_23

Theory : presheaf!models!of!type!theory


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