Rectification of Names (正名)

齊景公問政於孔子。 孔子對曰：「君君，臣臣，父父，子子。」

Duke Jǐng of Qí asked Confucius about government. Confucius replied "Let the ruler be a ruler; the minister, a minister; the father, a father; the son, a son."

-- The Analects 「論語」, 12:11.