Nuprl Lemma : W-subtype-coW
∀[A:𝕌']. ∀[B:A ⟶ Type].  (W(A;a.B[a]) ⊆r coW(A;a.B[a]))
Proof
Definitions occuring in Statement : 
coW: coW(A;a.B[a])
, 
W: W(A;a.B[a])
, 
subtype_rel: A ⊆r B
, 
uall: ∀[x:A]. B[x]
, 
so_apply: x[s]
, 
function: x:A ⟶ B[x]
, 
universe: Type
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
subtype_rel: A ⊆r B
, 
W: W(A;a.B[a])
, 
param-W: pW
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
, 
coW: coW(A;a.B[a])
Lemmas referenced : 
W_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
introduction, 
cut, 
lambdaEquality, 
sqequalHypSubstitution, 
setElimination, 
thin, 
rename, 
hypothesis, 
instantiate, 
extract_by_obid, 
isectElimination, 
hypothesisEquality, 
sqequalRule, 
cumulativity, 
applyEquality, 
axiomEquality, 
functionEquality, 
universeEquality, 
isect_memberEquality, 
because_Cache
Latex:
\mforall{}[A:\mBbbU{}'].  \mforall{}[B:A  {}\mrightarrow{}  Type].    (W(A;a.B[a])  \msubseteq{}r  coW(A;a.B[a]))
Date html generated:
2019_06_20-PM-00_56_01
Last ObjectModification:
2019_01_02-PM-01_32_37
Theory : co-recursion-2
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