Nuprl Lemma : presheaf-sigma_wf

[C:SmallCategory]. ∀[X:ps_context{j:l}(C)]. ∀[A:{X ⊢ _}]. ∀[B:{X.A ⊢ _}].  (Σ B ∈ X ⊢ )


Proof




Definitions occuring in Statement :  presheaf-sigma: Σ B psc-adjoin: X.A presheaf-type: {X ⊢ _} ps_context: __⊢ uall: [x:A]. B[x] member: t ∈ T small-category: SmallCategory
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T presheaf-sigma: Σ B presheaf-type: {X ⊢ _} subtype_rel: A ⊆B all: x:A. B[x] so_lambda: λ2x.t[x] so_apply: x[s] psc-restriction: f(s) pi2: snd(t) psc-adjoin: X.A psc-adjoin-set: (v;u) pi1: fst(t) and: P ∧ Q cand: c∧ B squash: T prop: true: True uimplies: supposing a guard: {T} iff: ⇐⇒ Q rev_implies:  Q implies:  Q
Lemmas referenced :  presheaf-type-at_wf psc-adjoin_wf ps_context_cumulativity2 presheaf-type-cumulativity2 psc-adjoin-set_wf I_set_wf cat-ob_wf presheaf-type-ap-morph_wf pi1_wf_top pi2_wf subtype_rel_self small-category-cumulativity-2 psc-restriction_wf cat-arrow_wf equal_wf squash_wf true_wf istype-universe cat-comp_wf presheaf-type-ap-morph-comp iff_weakening_equal presheaf-type-ap-morph-comp-eq psc-adjoin-set-restriction cat-id_wf subtype_rel-equal psc-restriction-id psc-restriction-comp presheaf-type_wf ps_context_wf small-category_wf presheaf-type-ap-morph-id
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation_alt introduction cut dependent_set_memberEquality_alt dependent_pairEquality_alt lambdaEquality_alt productEquality extract_by_obid sqequalHypSubstitution isectElimination thin hypothesisEquality hypothesis instantiate applyEquality because_Cache sqequalRule dependent_functionElimination universeIsType productElimination independent_pairEquality Error :memTop,  productIsType inhabitedIsType functionIsType lambdaFormation_alt independent_pairFormation imageElimination equalityTransitivity equalitySymmetry universeEquality natural_numberEquality imageMemberEquality baseClosed independent_isectElimination independent_functionElimination equalityIstype axiomEquality isect_memberEquality_alt isectIsTypeImplies

Latex:
\mforall{}[C:SmallCategory].  \mforall{}[X:ps\_context\{j:l\}(C)].  \mforall{}[A:\{X  \mvdash{}  \_\}].  \mforall{}[B:\{X.A  \mvdash{}  \_\}].    (\mSigma{}  A  B  \mmember{}  X  \mvdash{}  )



Date html generated: 2020_05_20-PM-01_31_23
Last ObjectModification: 2020_04_02-PM-03_03_10

Theory : presheaf!models!of!type!theory


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