Nuprl Lemma : functor-comp-assoc
∀[A,B,C,D:SmallCategory]. ∀[F:Functor(A;B)]. ∀[G:Functor(B;C)]. ∀[H:Functor(C;D)].
  (functor-comp(F;functor-comp(G;H)) = functor-comp(functor-comp(F;G);H) ∈ Functor(A;D))
Proof
Definitions occuring in Statement : 
functor-comp: functor-comp(F;G)
, 
cat-functor: Functor(C1;C2)
, 
small-category: SmallCategory
, 
uall: ∀[x:A]. B[x]
, 
equal: s = t ∈ T
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
uimplies: b supposing a
, 
functor-comp: functor-comp(F;G)
, 
all: ∀x:A. B[x]
, 
top: Top
, 
compose: f o g
Lemmas referenced : 
equal-functors, 
functor-comp_wf, 
functor-ob_wf, 
cat-ob_wf, 
functor-arrow_wf, 
cat-arrow_wf, 
cat-functor_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
introduction, 
cut, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
hypothesisEquality, 
hypothesis, 
independent_isectElimination, 
sqequalRule, 
dependent_functionElimination, 
isect_memberEquality, 
voidElimination, 
voidEquality, 
lambdaFormation, 
applyEquality, 
because_Cache, 
axiomEquality
Latex:
\mforall{}[A,B,C,D:SmallCategory].  \mforall{}[F:Functor(A;B)].  \mforall{}[G:Functor(B;C)].  \mforall{}[H:Functor(C;D)].
    (functor-comp(F;functor-comp(G;H))  =  functor-comp(functor-comp(F;G);H))
Date html generated:
2017_01_19-PM-02_53_35
Last ObjectModification:
2017_01_11-PM-10_13_16
Theory : small!categories
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