Nuprl Lemma : assert_equal
∀[a,b:𝔹].  uiff((↑a) = (↑b) ∈ Type;↑a ⇐⇒ ↑b)
Proof
Definitions occuring in Statement : 
assert: ↑b, 
bool: 𝔹, 
uiff: uiff(P;Q), 
uall: ∀[x:A]. B[x], 
iff: P ⇐⇒ Q, 
universe: Type, 
equal: s = t ∈ T
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x], 
member: t ∈ T, 
uiff: uiff(P;Q), 
and: P ∧ Q, 
uimplies: b supposing a, 
iff: P ⇐⇒ Q, 
implies: P ⇒ Q, 
guard: {T}, 
rev_implies: P ⇐ Q, 
prop: ℙ, 
squash: ↓T, 
true: True, 
subtype_rel: A ⊆r B
Lemmas referenced : 
bool_wf, 
iff_wf, 
iff_imp_equal_bool, 
equal_wf, 
assert_witness, 
assert_wf, 
iff_weakening_equal
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
introduction, 
cut, 
independent_pairFormation, 
lambdaFormation, 
hypothesis, 
equalitySymmetry, 
lemma_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
equalityTransitivity, 
independent_isectElimination, 
productElimination, 
independent_functionElimination, 
hypothesisEquality, 
sqequalRule, 
independent_pairEquality, 
lambdaEquality, 
dependent_functionElimination, 
instantiate, 
universeEquality, 
applyEquality, 
imageElimination, 
because_Cache, 
natural_numberEquality, 
imageMemberEquality, 
baseClosed, 
isect_memberEquality, 
axiomEquality
Latex:
\mforall{}[a,b:\mBbbB{}].    uiff((\muparrow{}a)  =  (\muparrow{}b);\muparrow{}a  \mLeftarrow{}{}\mRightarrow{}  \muparrow{}b)
Date html generated:
2016_05_13-PM-03_56_27
Last ObjectModification:
2016_01_14-PM-07_20_47
Theory : bool_1
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