Nuprl Lemma : fix_wf_coW_parameter
∀[P:Type]. ∀[A:𝕌']. ∀[B:A ⟶ Type]. ∀[G:⋂W:𝕌'. ((P ⟶ W) ⟶ P ⟶ (a:A × (B[a] ⟶ W)))]. ∀[p:P].
  (fix(G) p ∈ coW(A;a.B[a]))
Proof
Definitions occuring in Statement : 
coW: coW(A;a.B[a])
, 
uall: ∀[x:A]. B[x]
, 
so_apply: x[s]
, 
member: t ∈ T
, 
apply: f a
, 
fix: fix(F)
, 
isect: ⋂x:A. B[x]
, 
function: x:A ⟶ B[x]
, 
product: x:A × B[x]
, 
universe: Type
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
subtype_rel: A ⊆r B
, 
so_apply: x[s]
, 
so_lambda: λ2x.t[x]
, 
isect2: T1 ⋂ T2
, 
bool: 𝔹
, 
unit: Unit
, 
it: ⋅
, 
btrue: tt
, 
ifthenelse: if b then t else f fi 
, 
top: Top
, 
bfalse: ff
, 
ext-eq: A ≡ B
, 
and: P ∧ Q
Lemmas referenced : 
fix_wf_corec_parameter, 
top_wf, 
bool_wf, 
coW-corec
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
introduction, 
cut, 
applyEquality, 
hypothesis, 
sqequalHypSubstitution, 
sqequalRule, 
axiomEquality, 
equalityTransitivity, 
equalitySymmetry, 
hypothesisEquality, 
isect_memberEquality, 
isectElimination, 
thin, 
because_Cache, 
isectEquality, 
universeEquality, 
cumulativity, 
functionEquality, 
productEquality, 
instantiate, 
extract_by_obid, 
lambdaEquality, 
unionElimination, 
equalityElimination, 
functionExtensionality, 
voidElimination, 
voidEquality, 
productElimination
Latex:
\mforall{}[P:Type].  \mforall{}[A:\mBbbU{}'].  \mforall{}[B:A  {}\mrightarrow{}  Type].  \mforall{}[G:\mcap{}W:\mBbbU{}'.  ((P  {}\mrightarrow{}  W)  {}\mrightarrow{}  P  {}\mrightarrow{}  (a:A  \mtimes{}  (B[a]  {}\mrightarrow{}  W)))].  \mforall{}[p:P].
    (fix(G)  p  \mmember{}  coW(A;a.B[a]))
Date html generated:
2019_06_20-PM-00_56_05
Last ObjectModification:
2019_01_02-PM-01_32_43
Theory : co-recursion-2
Home
Index