English
Every atomic complete Boolean algebra is completely atomic.
Русский
Каждая атомарная полная булева алгебра completely atomic.
LaTeX
$$$\\text{CompleteBooleanAlgebra}(\\alpha) \\wedge \\text{IsAtomic}(\\alpha) \\Rightarrow \\text{CompleteAtomicBooleanAlgebra}(\\alpha)$$$
Lean4
/-- Every atomic complete Boolean algebra is completely atomic.
This is not made an instance to avoid typeclass loops. -/
-- See note [reducible non-instances]
abbrev toCompleteAtomicBooleanAlgebra {α} [CompleteBooleanAlgebra α] [IsAtomic α] : CompleteAtomicBooleanAlgebra α
where
__ := ‹CompleteBooleanAlgebra α›
iInf_iSup_eq
f := BooleanAlgebra.eq_iff_atom_le_iff.2 fun a ha => by simp only [le_iInf_iff, ha.le_iSup, Classical.skolem]