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
Home
Index