Nuprl Lemma : ps_contexts_equal
∀[C:SmallCategory]. ∀[X,Y:ps_context{j:l}(C)].
  X = Y ∈ ps_context{j:l}(C) 
  supposing X = Y ∈ (F:cat-ob(C) ⟶ 𝕌{j'} × (x:cat-ob(C) ⟶ y:cat-ob(C) ⟶ (cat-arrow(C) y x) ⟶ (F x) ⟶ (F y)))
Proof
Definitions occuring in Statement : 
ps_context: __⊢
, 
uimplies: b supposing a
, 
uall: ∀[x:A]. B[x]
, 
apply: f a
, 
function: x:A ⟶ B[x]
, 
product: x:A × B[x]
, 
universe: Type
, 
equal: s = t ∈ T
, 
cat-arrow: cat-arrow(C)
, 
cat-ob: cat-ob(C)
, 
small-category: SmallCategory
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
uimplies: b supposing a
, 
member: t ∈ T
, 
subtype_rel: A ⊆r B
, 
ps_context: __⊢
, 
cat-functor: Functor(C1;C2)
, 
small-category: SmallCategory
, 
spreadn: spread4, 
all: ∀x:A. B[x]
, 
type-cat: TypeCat
, 
op-cat: op-cat(C)
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
, 
pi1: fst(t)
, 
pi2: snd(t)
, 
and: P ∧ Q
, 
squash: ↓T
, 
prop: ℙ
, 
true: True
, 
guard: {T}
, 
iff: P 
⇐⇒ Q
, 
rev_implies: P 
⇐ Q
, 
implies: P 
⇒ Q
Lemmas referenced : 
equal-functors, 
op-cat_wf, 
type-cat_wf, 
small-category-cumulativity-2, 
cat_ob_pair_lemma, 
cat_arrow_triple_lemma, 
ob_pair_lemma, 
cat_id_tuple_lemma, 
cat_comp_tuple_lemma, 
pi2_wf, 
pi1_wf_top, 
arrow_pair_lemma, 
equal_wf, 
squash_wf, 
true_wf, 
istype-universe, 
subtype_rel_dep_function, 
subtype_rel-equal, 
subtype_rel_self, 
iff_weakening_equal, 
ps_context_wf, 
small-category_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation_alt, 
cut, 
thin, 
instantiate, 
introduction, 
extract_by_obid, 
hypothesis, 
sqequalHypSubstitution, 
isectElimination, 
hypothesisEquality, 
applyEquality, 
because_Cache, 
sqequalRule, 
independent_isectElimination, 
setElimination, 
rename, 
productElimination, 
dependent_functionElimination, 
Error :memTop, 
applyLambdaEquality, 
functionEquality, 
cumulativity, 
universeEquality, 
lambdaEquality_alt, 
inhabitedIsType, 
independent_pairEquality, 
lambdaFormation_alt, 
equalitySymmetry, 
dependent_set_memberEquality_alt, 
independent_pairFormation, 
equalityTransitivity, 
productIsType, 
equalityIstype, 
universeIsType, 
imageElimination, 
natural_numberEquality, 
imageMemberEquality, 
baseClosed, 
independent_functionElimination, 
functionIsType, 
dependent_pairEquality_alt
Latex:
\mforall{}[C:SmallCategory].  \mforall{}[X,Y:ps\_context\{j:l\}(C)].    X  =  Y  supposing  X  =  Y
Date html generated:
2020_05_20-PM-01_23_08
Last ObjectModification:
2020_04_02-PM-01_41_36
Theory : presheaf!models!of!type!theory
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