Nuprl Lemma : equipollent_weakening
∀[A,B:Type].  A ~ B supposing A = B ∈ Type
Proof
Definitions occuring in Statement : 
equipollent: A ~ B
, 
uimplies: b supposing a
, 
uall: ∀[x:A]. B[x]
, 
universe: Type
, 
equal: s = t ∈ T
Definitions unfolded in proof : 
equipollent: A ~ B
, 
uall: ∀[x:A]. B[x]
, 
uimplies: b supposing a
, 
member: t ∈ T
, 
exists: ∃x:A. B[x]
, 
prop: ℙ
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
Lemmas referenced : 
id-biject, 
biject_wf, 
exists_wf, 
equal_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalRule, 
sqequalReflexivity, 
sqequalTransitivity, 
computationStep, 
isect_memberFormation, 
cut, 
introduction, 
axiomEquality, 
hypothesis, 
thin, 
rename, 
dependent_pairFormation, 
lambdaEquality, 
hypothesisEquality, 
cumulativity, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
functionExtensionality, 
applyEquality, 
hyp_replacement, 
equalitySymmetry, 
Error :applyLambdaEquality, 
functionEquality, 
instantiate, 
universeEquality
Latex:
\mforall{}[A,B:Type].    A  \msim{}  B  supposing  A  =  B
Date html generated:
2016_10_21-AM-10_51_53
Last ObjectModification:
2016_07_12-AM-05_55_49
Theory : equipollence!!cardinality!
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