Nuprl Lemma : uall_functionality_wrt_iff
∀[S,T:Type]. ∀[P,Q:S ⟶ ℙ].  (∀[x:S]. (P[x] 
⇐⇒ Q[x])) 
⇒ {∀[x:S]. P[x] 
⇐⇒ ∀[y:T]. Q[y]} supposing S = T ∈ Type
Proof
Definitions occuring in Statement : 
uimplies: b supposing a
, 
uall: ∀[x:A]. B[x]
, 
prop: ℙ
, 
guard: {T}
, 
so_apply: x[s]
, 
iff: P 
⇐⇒ Q
, 
implies: P 
⇒ Q
, 
function: x:A ⟶ B[x]
, 
universe: Type
, 
equal: s = t ∈ T
Definitions unfolded in proof : 
guard: {T}
, 
member: t ∈ T
, 
uall: ∀[x:A]. B[x]
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
, 
iff: P 
⇐⇒ Q
, 
implies: P 
⇒ Q
, 
prop: ℙ
, 
rev_implies: P 
⇐ Q
, 
subtype_rel: A ⊆r B
, 
uimplies: b supposing a
, 
and: P ∧ Q
Lemmas referenced : 
equal_wf, 
and_wf, 
uall_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalRule, 
sqequalReflexivity, 
sqequalTransitivity, 
computationStep, 
hyp_replacement, 
hypothesisEquality, 
equalitySymmetry, 
hypothesis, 
cut, 
lemma_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
lambdaEquality, 
applyEquality, 
cumulativity, 
because_Cache, 
functionEquality, 
universeEquality, 
instantiate, 
isect_memberFormation, 
introduction, 
axiomEquality, 
rename, 
lambdaFormation, 
independent_pairFormation, 
productElimination, 
independent_functionElimination
Latex:
\mforall{}[S,T:Type].  \mforall{}[P,Q:S  {}\mrightarrow{}  \mBbbP{}].
    (\mforall{}[x:S].  (P[x]  \mLeftarrow{}{}\mRightarrow{}  Q[x]))  {}\mRightarrow{}  \{\mforall{}[x:S].  P[x]  \mLeftarrow{}{}\mRightarrow{}  \mforall{}[y:T].  Q[y]\}  supposing  S  =  T
Date html generated:
2016_05_13-PM-03_07_43
Last ObjectModification:
2016_01_06-PM-05_28_05
Theory : core_2
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