Nuprl Lemma : subset-presheaf-type

[C:SmallCategory]. ∀[X,Y:ps_context{j:l}(C)].  {X ⊢ _} ⊆{Y ⊢ _} supposing sub_ps_context{j:l}(C; Y; X)


Proof




Definitions occuring in Statement :  presheaf-type: {X ⊢ _} sub_ps_context: Y ⊆ X ps_context: __⊢ uimplies: supposing a subtype_rel: A ⊆B uall: [x:A]. B[x] small-category: SmallCategory
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T uimplies: supposing a subtype_rel: A ⊆B sub_ps_context: Y ⊆ X presheaf-type: {X ⊢ _} so_lambda: λ2x.t[x] so_apply: x[s] all: x:A. B[x] squash: T prop: true: True guard: {T} iff: ⇐⇒ Q and: P ∧ Q rev_implies:  Q implies:  Q pscm-id: 1(X) pscm-ap-type: (AF)s pscm-ap: (s)x
Lemmas referenced :  subset-I_set ps-subset-restriction presheaf-type-equal pscm-ap-type_wf subtype_rel_product cat-ob_wf I_set_wf cat-arrow_wf psc-restriction_wf istype-universe subtype_rel_dep_function subtype_rel-equal equal_wf squash_wf true_wf subtype_rel_self iff_weakening_equal presheaf-type_wf sub_ps_context_wf ps_context_wf small-category-cumulativity-2 small-category_wf
Rules used in proof :  cut introduction extract_by_obid sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation_alt hypothesis sqequalHypSubstitution isectElimination thin hypothesisEquality independent_isectElimination lambdaEquality_alt setElimination rename applyEquality instantiate functionEquality cumulativity universeEquality sqequalRule functionIsType universeIsType because_Cache lambdaFormation_alt dependent_functionElimination inhabitedIsType imageElimination equalityTransitivity equalitySymmetry natural_numberEquality imageMemberEquality baseClosed productElimination independent_functionElimination dependent_pairEquality_alt axiomEquality functionExtensionality hyp_replacement

Latex:
\mforall{}[C:SmallCategory].  \mforall{}[X,Y:ps\_context\{j:l\}(C)].
    \{X  \mvdash{}  \_\}  \msubseteq{}r  \{Y  \mvdash{}  \_\}  supposing  sub\_ps\_context\{j:l\}(C;  Y;  X)



Date html generated: 2020_05_20-PM-01_35_00
Last ObjectModification: 2020_04_02-PM-06_34_43

Theory : presheaf!models!of!type!theory


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