Lü Dai
Xu Yuan was known for being loyal, bold and outspoken. Whenever he saw Lü Dai make a mistake, he would point it out to Lü Dai in private and, at the same time, bring up the issue and discuss it in public. When someone told Lü Dai about it, the latter remarked: "This is why I regard Deyuan (Xu Yuan's courtesy name) so highly."