《庄子·外篇·达生》
田开之拜见周威公。周威公说： 我听说祝肾在学习养生，先生跟祝肾交往，应该从他那儿听到过什么吧？ 
田开之见周威公，威公曰： 吾闻祝肾学生，吾子与祝肾游，亦何闻焉？ 
Tian Kai went to visit Zhou Weigong. Zhou Weigong said: I heard that Zhu Shen is learning how to cultivate life, Sir must have heard something from him?