Nuprl Lemma : cat-comp-ident

[C:SmallCategory]
  ∀x,y:cat-ob(C). ∀f:cat-arrow(C) y.
    (((cat-comp(C) (cat-id(C) x) f) f ∈ (cat-arrow(C) y))
    ∧ ((cat-comp(C) (cat-id(C) y)) f ∈ (cat-arrow(C) y)))


Proof




Definitions occuring in Statement :  cat-comp: cat-comp(C) cat-id: cat-id(C) cat-arrow: cat-arrow(C) cat-ob: cat-ob(C) small-category: SmallCategory uall: [x:A]. B[x] all: x:A. B[x] and: P ∧ Q apply: a equal: t ∈ T
Definitions unfolded in proof :  guard: {T} cand: c∧ B and: P ∧ Q spreadn: spread4 cat-comp: cat-comp(C) cat-id: cat-id(C) cat-ob: cat-ob(C) pi1: fst(t) pi2: snd(t) cat-arrow: cat-arrow(C) small-category: SmallCategory all: x:A. B[x] member: t ∈ T uall: [x:A]. B[x]
Lemmas referenced :  small-category_wf cat-ob_wf cat-arrow_wf
Rules used in proof :  because_Cache axiomEquality independent_pairEquality dependent_functionElimination lambdaEquality hypothesisEquality isectElimination lemma_by_obid applyEquality hypothesis independent_pairFormation sqequalRule productElimination rename thin setElimination sqequalHypSubstitution lambdaFormation cut introduction isect_memberFormation sqequalReflexivity computationStep sqequalTransitivity sqequalSubstitution

Latex:
\mforall{}[C:SmallCategory]
    \mforall{}x,y:cat-ob(C).  \mforall{}f:cat-arrow(C)  x  y.
        (((cat-comp(C)  x  x  y  (cat-id(C)  x)  f)  =  f)  \mwedge{}  ((cat-comp(C)  x  y  y  f  (cat-id(C)  y))  =  f))



Date html generated: 2020_05_20-AM-07_50_00
Last ObjectModification: 2015_12_28-PM-02_23_55

Theory : small!categories


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