Nuprl Lemma : discrete-presheaf-term_wf

[C:SmallCategory]. ∀[T:Type]. ∀[t:T]. ∀[X:ps_context{j:l}(C)].  (discr(t) ∈ {X ⊢ _:discr(T)})


Proof




Definitions occuring in Statement :  discrete-presheaf-term: discr(t) discrete-presheaf-type: discr(T) presheaf-term: {X ⊢ _:A} ps_context: __⊢ uall: [x:A]. B[x] member: t ∈ T universe: Type small-category: SmallCategory
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T discrete-presheaf-term: discr(t) discrete-presheaf-type: discr(T) presheaf-term: {X ⊢ _:A} presheaf-type-at: A(a) pi1: fst(t) presheaf-type-ap-morph: (u f) pi2: snd(t) all: x:A. B[x] subtype_rel: A ⊆B
Lemmas referenced :  I_set_wf cat-ob_wf cat-arrow_wf psc-restriction_wf ps_context_wf small-category-cumulativity-2 istype-universe small-category_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation_alt introduction cut dependent_set_memberEquality_alt sqequalRule lambdaEquality_alt hypothesisEquality universeIsType extract_by_obid sqequalHypSubstitution isectElimination thin hypothesis lambdaFormation_alt applyEquality inhabitedIsType functionIsType because_Cache equalityIstype axiomEquality equalityTransitivity equalitySymmetry instantiate isect_memberEquality_alt isectIsTypeImplies universeEquality

Latex:
\mforall{}[C:SmallCategory].  \mforall{}[T:Type].  \mforall{}[t:T].  \mforall{}[X:ps\_context\{j:l\}(C)].    (discr(t)  \mmember{}  \{X  \mvdash{}  \_:discr(T)\})



Date html generated: 2020_05_20-PM-01_34_11
Last ObjectModification: 2020_04_02-PM-06_33_06

Theory : presheaf!models!of!type!theory


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