Nuprl Lemma : slice-cat_wf

[C:SmallCategory]. ∀[x:cat-ob(C)].  ((C ↓ x) ∈ SmallCategory)


Proof




Definitions occuring in Statement :  slice-cat: (C ↓ b) cat-ob: cat-ob(C) small-category: SmallCategory uall: [x:A]. B[x] member: t ∈ T
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T slice-cat: (C ↓ b)
Lemmas referenced :  comma-slice-cat_wf id_functor_wf cat-ob_wf small-category_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation introduction cut sqequalRule extract_by_obid sqequalHypSubstitution isectElimination thin hypothesisEquality hypothesis axiomEquality equalityTransitivity equalitySymmetry isect_memberEquality because_Cache

Latex:
\mforall{}[C:SmallCategory].  \mforall{}[x:cat-ob(C)].    ((C  \mdownarrow{}  x)  \mmember{}  SmallCategory)



Date html generated: 2020_05_20-AM-07_56_43
Last ObjectModification: 2017_01_13-PM-04_53_02

Theory : small!categories


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