"Similarly, the term luan (often translated as 'disorder' or 'chaos,'
and rendered as 'revolution' by Arthur Waley in the passage from
Analects quoted above) implies the perversion of sexual, familial, and
political order; it appears in compounds meaning 'incest' (e.g. luan
lun) and 'rebellion' (pan luan). One of the 'Ten Abominations' (shi e)
enumerated at the beginning of every legal code from the Tang dynasty
forward is nei luan, literally, 'internal disorder.' In a legal
context, nei luan refers to incest, but it can dean rebellion or civil
war as well. The director Kurosawa Akira captured this range of
nuances in his 1985 film Ran (the Japanese pronunciation of luan),
which is loosely based on King Lear. In Kurosawa's vision of luan,
when sons are set over their father, feudal order falls apart --
devolving into a nightmare of fratricide, patricide, incest, betrayal
or husband and wife, and finally civil war.
The connection between sexual and political disorder was not just a
question of semantics or of Confucian abstraction…"
Matthew H. Sommer, Sex, Law, and Society in Late Imperial China
(Kindle edition, 2000), 8% into the book.