From
《论语·颜渊》 (Analects: Yan Yuan). Confucius tells Ji Kangzi:
君子之德风,
小人之德草。
草上之风,
必偃 - 'the gentleman's virtue is wind, the common person's virtue is grass. When the wind passes over the grass, the grass must bend.' A classic Confucian image for moral leadership through example rather than command.