Nuprl Lemma : subtype-iff-id-mem-fun
∀[A,B:Type].  uiff(A ⊆r B;λx.x ∈ A ⟶ B)
Proof
Definitions occuring in Statement : 
uiff: uiff(P;Q)
, 
subtype_rel: A ⊆r B
, 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
lambda: λx.A[x]
, 
function: x:A ⟶ B[x]
, 
universe: Type
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
uiff: uiff(P;Q)
, 
and: P ∧ Q
, 
uimplies: b supposing a
, 
subtype_rel: A ⊆r B
, 
prop: ℙ
Lemmas referenced : 
equal-wf-base, 
subtype_rel_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
introduction, 
cut, 
independent_pairFormation, 
lambdaEquality, 
hypothesisEquality, 
applyEquality, 
hypothesis, 
sqequalHypSubstitution, 
sqequalRule, 
axiomEquality, 
equalityTransitivity, 
equalitySymmetry, 
lemma_by_obid, 
isectElimination, 
thin, 
functionEquality, 
baseClosed, 
because_Cache, 
productElimination, 
independent_pairEquality, 
isect_memberEquality, 
universeEquality
Latex:
\mforall{}[A,B:Type].    uiff(A  \msubseteq{}r  B;\mlambda{}x.x  \mmember{}  A  {}\mrightarrow{}  B)
Date html generated:
2016_05_13-PM-04_14_14
Last ObjectModification:
2016_01_14-PM-07_28_45
Theory : subtype_1
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