Nuprl Lemma : product-cat_wf

∀[A,B:SmallCategory].  (A × B ∈ SmallCategory)


Proof




Definitions occuring in Statement :  product-cat: A × B,  small-category: SmallCategory,  uall: ∀[x:A]. B[x],  member: t ∈ T
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  small-category: SmallCategory,  product-cat: A × B,  pi1: fst(t),  pi2: snd(t),  spreadn: spread4,  and: P ∧ Q,  all: ∀x:A. B[x],  cand: A c∧ B,  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,  so_lambda: λ2x.t[x],  so_apply: x[s],  top: Top
Lemmas referenced :  small-category_wf,  cat-ob_wf,  cat-arrow_wf,  cat-id_wf,  cat-comp_wf,  equal_wf,  squash_wf,  true_wf,  cat-comp-ident1,  iff_weakening_equal,  cat-comp-ident2,  cat-comp-assoc,  pi2_wf,  pi1_wf_top,  all_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  dependent_set_memberEquality,  cut,  introduction,  extract_by_obid,  hypothesis,  dependent_pairEquality,  productEquality,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesisEquality,  functionEquality,  cumulativity,  universeEquality,  applyEquality,  functionExtensionality,  lambdaEquality,  productElimination,  sqequalRule,  because_Cache,  independent_pairEquality,  independent_pairFormation,  lambdaFormation,  imageElimination,  equalityTransitivity,  equalitySymmetry,  dependent_functionElimination,  natural_numberEquality,  imageMemberEquality,  baseClosed,  independent_isectElimination,  independent_functionElimination,  isect_memberEquality,  voidElimination,  voidEquality

Latex:
\mforall{}[A,B:SmallCategory].    (A  \mtimes{}  B  \mmember{}  SmallCategory)



Date html generated: 2017_10_05-AM-00_47_54
Last ObjectModification: 2017_07_28-AM-09_19_50

Theory : small!categories


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