Five sons in the Three-Character Classics: Xunzi, Yangzi (Yang Zhu), Wenzhongzi (Wang Tong), Laozi and Zhuangzi.
The original text is: Five sons have Xunyang. Wen Zhongzi and Lao Zhuang. Jing Zitong, reading history.
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The answer is: a Mencius.
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