Nuprl Lemma : equal-presheaves
∀[C:SmallCategory]. ∀[F,G:Presheaf(C)].
  F = G ∈ Presheaf(C) 
  supposing (∀x:cat-ob(op-cat(C)). ((ob(F) x) = (ob(G) x) ∈ cat-ob(TypeCat)))
  ∧ (∀x,y:cat-ob(op-cat(C)). ∀f:cat-arrow(op-cat(C)) x y.
       ((arrow(F) x y f) = (arrow(G) x y f) ∈ (cat-arrow(TypeCat) (ob(F) x) (ob(F) y))))
Proof
Definitions occuring in Statement : 
presheaf: Presheaf(C)
, 
type-cat: TypeCat
, 
op-cat: op-cat(C)
, 
functor-arrow: arrow(F)
, 
functor-ob: ob(F)
, 
cat-arrow: cat-arrow(C)
, 
cat-ob: cat-ob(C)
, 
small-category: SmallCategory
, 
uimplies: b supposing a
, 
uall: ∀[x:A]. B[x]
, 
all: ∀x:A. B[x]
, 
and: P ∧ Q
, 
apply: f a
, 
equal: s = t ∈ T
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
uimplies: b supposing a
, 
and: P ∧ Q
, 
presheaf: Presheaf(C)
, 
subtype_rel: A ⊆r B
, 
prop: ℙ
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
, 
all: ∀x:A. B[x]
, 
squash: ↓T
, 
true: True
, 
guard: {T}
, 
iff: P 
⇐⇒ Q
, 
rev_implies: P 
⇐ Q
, 
implies: P 
⇒ Q
Lemmas referenced : 
equal-functors, 
op-cat_wf, 
type-cat_wf, 
all_wf, 
cat-ob_wf, 
equal_wf, 
functor-ob_wf, 
small-category-subtype, 
cat-arrow_wf, 
functor-arrow_wf, 
subtype_rel-equal, 
squash_wf, 
true_wf, 
iff_weakening_equal, 
presheaf_wf, 
small-category_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
introduction, 
cut, 
sqequalHypSubstitution, 
productElimination, 
thin, 
instantiate, 
extract_by_obid, 
isectElimination, 
hypothesisEquality, 
applyEquality, 
because_Cache, 
hypothesis, 
sqequalRule, 
independent_isectElimination, 
productEquality, 
lambdaEquality, 
cumulativity, 
universeEquality, 
imageElimination, 
equalityTransitivity, 
equalitySymmetry, 
dependent_functionElimination, 
natural_numberEquality, 
imageMemberEquality, 
baseClosed, 
independent_functionElimination, 
isect_memberEquality, 
axiomEquality
Latex:
\mforall{}[C:SmallCategory].  \mforall{}[F,G:Presheaf(C)].
    F  =  G 
    supposing  (\mforall{}x:cat-ob(op-cat(C)).  ((ob(F)  x)  =  (ob(G)  x)))
    \mwedge{}  (\mforall{}x,y:cat-ob(op-cat(C)).  \mforall{}f:cat-arrow(op-cat(C))  x  y.    ((arrow(F)  x  y  f)  =  (arrow(G)  x  y  f)))
Date html generated:
2017_10_05-AM-00_47_28
Last ObjectModification:
2017_10_03-PM-02_24_56
Theory : small!categories
Home
Index