Nuprl Lemma : discrete-presheaf-type_wf
∀[C:SmallCategory]. ∀[T:Type]. ∀[X:ps_context{j:l}(C)].  (discr(T) ∈ X ⊢ )
Proof
Definitions occuring in Statement : 
discrete-presheaf-type: discr(T), 
presheaf-type: {X ⊢ _}, 
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, 
presheaf-type: {X ⊢ _}, 
discrete-presheaf-type: discr(T), 
and: P ∧ Q, 
cand: A c∧ B, 
all: ∀x:A. B[x], 
subtype_rel: A ⊆r B, 
uimplies: b supposing a, 
squash: ↓T, 
prop: ℙ, 
true: True, 
guard: {T}, 
iff: P ⇐⇒ Q, 
rev_implies: P ⇐ Q, 
implies: P ⇒ Q
Lemmas referenced : 
I_set_wf, 
cat-ob_wf, 
cat-arrow_wf, 
psc-restriction_wf, 
cat-id_wf, 
subtype_rel-equal, 
equal_wf, 
squash_wf, 
true_wf, 
istype-universe, 
psc-restriction-id, 
subtype_rel_self, 
iff_weakening_equal, 
cat-comp_wf, 
psc-restriction-comp, 
ps_context_wf, 
small-category-cumulativity-2, 
small-category_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation_alt, 
introduction, 
cut, 
dependent_set_memberEquality_alt, 
dependent_pairEquality_alt, 
lambdaEquality_alt, 
hypothesisEquality, 
universeIsType, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
hypothesis, 
sqequalRule, 
because_Cache, 
applyEquality, 
inhabitedIsType, 
functionIsType, 
lambdaFormation_alt, 
independent_pairFormation, 
productElimination, 
productIsType, 
equalityIstype, 
independent_isectElimination, 
instantiate, 
imageElimination, 
equalityTransitivity, 
equalitySymmetry, 
universeEquality, 
natural_numberEquality, 
imageMemberEquality, 
baseClosed, 
independent_functionElimination, 
dependent_functionElimination, 
axiomEquality, 
isect_memberEquality_alt, 
isectIsTypeImplies
Latex:
\mforall{}[C:SmallCategory].  \mforall{}[T:Type].  \mforall{}[X:ps\_context\{j:l\}(C)].    (discr(T)  \mmember{}  X  \mvdash{}  )
Date html generated:
2020_05_20-PM-01_34_07
Last ObjectModification:
2020_04_02-PM-06_32_56
Theory : presheaf!models!of!type!theory
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