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
Home
Index