Nuprl Lemma : sub_ps_context_functionality

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


Proof




Definitions occuring in Statement :  psc-adjoin: X.A,  presheaf-type: {X ⊢ _},  sub_ps_context: Y ⊆ X,  ps_context: __⊢,  uimplies: b supposing a,  uall: ∀[x:A]. B[x],  small-category: SmallCategory
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  uimplies: b supposing a,  subtype_rel: A ⊆r B,  psc-adjoin: X.A,  all: ∀x:A. B[x],  so_lambda: λ2x.t[x],  so_apply: x[s],  istype: istype(T),  squash: ↓T,  prop: ℙ,  true: True,  guard: {T},  iff: P ⇐⇒ Q,  and: P ∧ Q,  rev_implies: P ⇐ Q,  implies: P ⇒ Q,  sub_ps_context: Y ⊆ X
Lemmas referenced :  implies-sub_ps_context,  psc-adjoin_wf,  small-category-cumulativity-2,  ps_context_cumulativity2,  presheaf-type-cumulativity2,  I_set_pair_redex_lemma,  subtype_rel_product,  I_set_wf,  presheaf-type-at_wf,  subset-presheaf-type,  subset-I_set,  cat-ob_wf,  psc_restriction_pair_lemma,  equal_wf,  squash_wf,  true_wf,  istype-universe,  ps-subset-restriction,  pi1_wf_top,  psc-restriction_wf,  subtype_rel_self,  iff_weakening_equal,  presheaf-type-ap-morph_wf,  pi2_wf,  cat-arrow_wf,  sub_ps_context_wf,  presheaf-type_wf,  ps_context_wf,  small-category_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation_alt,  introduction,  cut,  thin,  instantiate,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  hypothesisEquality,  applyEquality,  hypothesis,  sqequalRule,  because_Cache,  independent_isectElimination,  dependent_functionElimination,  Error :memTop,  lambdaFormation_alt,  cumulativity,  lambdaEquality_alt,  universeIsType,  dependent_pairEquality_alt,  imageElimination,  equalityTransitivity,  equalitySymmetry,  universeEquality,  productElimination,  independent_pairEquality,  natural_numberEquality,  imageMemberEquality,  baseClosed,  independent_functionElimination,  productIsType,  axiomEquality,  isect_memberEquality_alt,  isectIsTypeImplies,  inhabitedIsType

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



Date html generated: 2020_05_20-PM-01_35_27
Last ObjectModification: 2020_04_03-AM-01_23_09

Theory : presheaf!models!of!type!theory


Home Index