Nuprl Lemma : fan-iff-wkl!
Fan 
⇐⇒ WKL!
Proof
Definitions occuring in Statement : 
wkl!: WKL!
, 
fan: Fan
, 
iff: P 
⇐⇒ Q
Definitions unfolded in proof : 
all: ∀x:A. B[x]
, 
member: t ∈ T
, 
implies: P 
⇒ Q
, 
iff: P 
⇐⇒ Q
, 
and: P ∧ Q
, 
rev_implies: P 
⇐ Q
, 
prop: ℙ
, 
uall: ∀[x:A]. B[x]
, 
exists: ∃x:A. B[x]
, 
nat: ℕ
, 
le: A ≤ B
, 
less_than': less_than'(a;b)
, 
false: False
, 
not: ¬A
Lemmas referenced : 
dfan-iff-twkl!, 
bool_wf, 
fan-iff-dfan-bool, 
wkl!-iff-twkl!-bool, 
fan_wf, 
wkl!_wf, 
iff_wf, 
dfan_wf, 
twkl!_wf, 
false_wf, 
le_wf, 
equipollent-two, 
equipollent_wf, 
int_seg_wf
Rules used in proof : 
cut, 
lemma_by_obid, 
sqequalHypSubstitution, 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
dependent_functionElimination, 
thin, 
hypothesis, 
independent_functionElimination, 
addLevel, 
productElimination, 
independent_pairFormation, 
impliesFunctionality, 
instantiate, 
isectElimination, 
dependent_pairFormation, 
dependent_set_memberEquality, 
natural_numberEquality, 
sqequalRule, 
lambdaFormation, 
hypothesisEquality, 
setElimination, 
rename
Latex:
Fan  \mLeftarrow{}{}\mRightarrow{}  WKL!
Date html generated:
2016_05_14-PM-04_12_50
Last ObjectModification:
2015_12_26-PM-07_53_58
Theory : fan-theorem
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