When music is performed in the ancestral temple of the ruler,
and the ruler and his ministers, superiors and inferiors, listen to it together,
there are none who are not filled with a spirit of harmonious reverence.
When it is performed within the household,
and father and sons, elder and younger brothers listen to it together,
there are none who are not filled with a spirit of harmonious kinship.
And when it is performed in the community,
and old people and young together listen to it,
there are none who are not filled with a spirit of harmonious obedience.
Hence music brings about complete unity and induces harmony.
It arranges its accouterments to comprise an adornment to moderation;
it blends its performance to achieve the completion of form.
It is sufficient to lead men in the single Way
or to bring order to ten thousand changes.
This is the manner in which the former kings created their music.

--Xunzi, "Discussion of Music"
translated by Burton Watson

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