Nuprl Lemma : iff_imp_equal_bool
∀[a,b:𝔹].  a = b supposing ↑a ⇐⇒ ↑b
Proof
Definitions occuring in Statement : 
assert: ↑b, 
bool: 𝔹, 
uimplies: b supposing a, 
uall: ∀[x:A]. B[x], 
iff: P ⇐⇒ Q, 
equal: s = t ∈ T
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x], 
member: t ∈ T, 
uimplies: b supposing a, 
iff: P ⇐⇒ Q, 
and: P ∧ Q, 
implies: P ⇒ Q, 
prop: ℙ, 
rev_implies: P ⇐ Q, 
false: False, 
true: True, 
bfalse: ff, 
ifthenelse: if b then t else f fi , 
assert: ↑b, 
btrue: tt, 
it: ⋅, 
unit: Unit, 
bool: 𝔹
Lemmas referenced : 
assert_wf, 
iff_wf, 
bool_wf, 
bfalse_wf, 
btrue_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
Error :isect_memberFormation_alt, 
introduction, 
cut, 
hypothesis, 
sqequalRule, 
Error :productIsType, 
Error :functionIsType, 
Error :universeIsType, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
hypothesisEquality, 
because_Cache, 
isect_memberEquality, 
axiomEquality, 
equalityTransitivity, 
equalitySymmetry, 
Error :inhabitedIsType, 
voidElimination, 
natural_numberEquality, 
independent_functionElimination, 
productElimination, 
equalityElimination, 
unionElimination
Latex:
\mforall{}[a,b:\mBbbB{}].    a  =  b  supposing  \muparrow{}a  \mLeftarrow{}{}\mRightarrow{}  \muparrow{}b
Date html generated:
2019_06_20-AM-11_31_25
Last ObjectModification:
2018_09_26-AM-11_16_10
Theory : bool_1
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