Nuprl Lemma : cat-comp-assoc

∀[C:SmallCategory]
  ∀x,y,z,w:cat-ob(C). ∀f:cat-arrow(C) x y. ∀g:cat-arrow(C) y z. ∀h:cat-arrow(C) z w.
    ((cat-comp(C) x z w (cat-comp(C) x y z f g) h) = (cat-comp(C) x y w f (cat-comp(C) y z w g h)) ∈ (cat-arrow(C) x w))


Proof




Definitions occuring in Statement :  cat-comp: cat-comp(C),  cat-arrow: cat-arrow(C),  cat-ob: cat-ob(C),  small-category: SmallCategory,  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  apply: f a,  equal: s = t ∈ T
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  all: ∀x:A. B[x],  small-category: SmallCategory,  cat-arrow: cat-arrow(C),  pi2: snd(t),  pi1: fst(t),  cat-ob: cat-ob(C),  cat-comp: cat-comp(C),  spreadn: spread4,  and: P ∧ Q,  squash: ↓T,  prop: ℙ,  true: True,  subtype_rel: A ⊆r B,  uimplies: b supposing a,  guard: {T},  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  implies: P ⇒ Q
Lemmas referenced :  equal_wf,  squash_wf,  true_wf,  iff_weakening_equal,  cat-arrow_wf,  cat-ob_wf,  small-category_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  lambdaFormation,  sqequalHypSubstitution,  setElimination,  thin,  rename,  productElimination,  sqequalRule,  applyEquality,  lambdaEquality,  imageElimination,  extract_by_obid,  isectElimination,  hypothesisEquality,  equalityTransitivity,  hypothesis,  equalitySymmetry,  universeEquality,  functionExtensionality,  cumulativity,  dependent_functionElimination,  because_Cache,  natural_numberEquality,  imageMemberEquality,  baseClosed,  independent_isectElimination,  independent_functionElimination,  axiomEquality

Latex:
\mforall{}[C:SmallCategory]
    \mforall{}x,y,z,w:cat-ob(C).  \mforall{}f:cat-arrow(C)  x  y.  \mforall{}g:cat-arrow(C)  y  z.  \mforall{}h:cat-arrow(C)  z  w.
        ((cat-comp(C)  x  z  w  (cat-comp(C)  x  y  z  f  g)  h)  =  (cat-comp(C)  x  y  w  f  (cat-comp(C)  y  z  w  g  h)))



Date html generated: 2020_05_20-AM-07_49_57
Last ObjectModification: 2017_07_28-AM-09_18_59

Theory : small!categories


Home Index