Today’s page in Deng Ming-Dao’s The Lunar Tao deals with “Customs.” He quotes The Record of Rites, one of the five Confucian classics said to have been compiled by Confucius himself in the 6th or 5th century BCE, on the importance of preserving customs even when living in foreign countries:
When a superior person practices the rites [in another country], he does not change his own customs. His sacrifices and worship are proper. His dress when mourning and his posture in waiting and weeping will accord with the customs of his home nation. He will carefully study the rules, and practice them exactly.
Even if he has been away from the country for three generations, if his title is still accorded to him at the court, and his activities are still reported to the state, if his brothers, cousins, and clan remain, he should continue to send reports about himself to the head of the family.
Even if he has been away from the country for three generations, even if his title is not accorded to him at the court, and even if his activities are not reported to the state, it is only on the day of his establishment [to a rank in the new nation] that he should follow the customs of his new country. (78)