Corollary 2
Tag 0A0I, permanent. Cite it as [Bourbaki, Tag 0A0I].
Lie Groups and Lie Algebras, chapter I, § 6. Semi-simple Lie algebras
For a subalgebra h of g to be a Levi subalgebra of g, it is necessary and sufficient that h be a maximal semi-simple subalgebra of g.
This follows immediately from Corollary 1.
Bourbaki puts the proof directly after the statement, so what is above is the statement and its proof together.
Cited by
Nothing.