A neighbour of Yang Zhu lost a sheep. This neighbour took his family and friends with him, and also asked Yang Zhu to send his servants to help track down the sheep. Yang Zhu said, ‘It’s only one lost sheep—why do you need so many people to go after it?’ The neighbour replied, ‘Because there are so many forks in the road.’
When the search party returned, Yang Zhu asked, ‘Have you found the sheep?’ The neighbour said, ‘It’s gone; we couldn’t catch up with it.’ Yang Zhu asked, ‘Why couldn’t you catch up with it?’ The neighbour said, ‘Among the forks in the road, there were yet more forks; I didn’t know which way to go, so I came back.’
Upon hearing this, Yang Zhu’s expression turned sombre; he remained silent for a long time and did not smile all day. His disciples found this strange and asked, ‘A sheep is a worthless animal, and it does not even belong to you, Master. Why have you not smiled all day?’ Yang Zhu gave no reply.
Afterwards, his disciple Mengsun Yang went out and recounted this incident to Xindu Zi. A few days later, Xindu Zi and Mengsun Yang came together to see Yang Zhu. Xindu Zi asked, ‘ ‘In the past, there were three brothers who travelled through the regions of Qi and Lu. They studied under the same teacher and, having mastered the principles of benevolence and righteousness, returned home. Their father asked, “What is the nature of the benevolence and righteousness you have learnt?” The eldest said, “Benevolence and righteousness lead me to cherish life and place reputation second.” The second said, “Benevolence and righteousness enable me to sacrifice my life to achieve fame.” The youngest said, “ Benevolence and righteousness enable me to preserve my life while also gaining reputation throughout the land.’ Their views were very different, yet all three came from the same Confucian school. In your opinion, who is right and who is wrong?”
Yang Zhu replied: “There was a man living by the river who was skilled at swimming; he earned his living by ferrying people across the river, supporting a household of over a hundred people. Members of his clan sought to learn swimming from him, but many of them drowned. Those people had originally gone to learn to swim, not to learn how to drown, yet the consequences were so vastly different. As for the three brothers you mentioned just now, who is right and who is wrong?” Upon hearing this, Xindu Zi walked out without uttering a word.
Once outside, Xindu Zi said to Mengsun Yang: ‘There is only one sheep, yet it is lost because there are too many forked paths; The same holds true for pursuing knowledge and cultivating the Tao. Knowledge was originally a single entity, rooted in oneness. Yet, the more minutely it is categorized, the more its essence vanishes. Only by tracing back to the common origin and returning to the sole truth will it not be lost. You have studied under your teacher for so long, learning his doctrines, yet you do not understand the profound meaning of this parable. How truly lamentable!”
Origin: “Liezi: Shuo Fu”
#59 歧路亡羊
杨朱的邻居丢了一只羊，这个邻居带了自己的家人和亲友，还请求杨朱派家仆一起去帮忙追那只羊。杨朱说：“哎呀！只丢了一只羊，为什么要这么多人去追呢？”邻居回答：“因为岔路太多了。”
寻羊的人回来后，杨朱问：“找到羊了吗？”邻居说：“丢了，追不到了。”杨朱问：“怎么追不到呢？”邻居说：“岔路之中还有岔路，我不知道该往哪条路走，所以就回来了。”
杨朱听后脸色变得忧伤，沉默了很久，整天都没有笑容。学生们感到奇怪，便问：“羊是不值钱的牲畜，又不是老师您的，为什么您一天都没有笑容呢？”杨朱没有回答。
弟子孟孙阳出来后，把这件事告诉了心都子。过了几天，心都子和孟孙阳一同来见杨朱，心都子问道：“从前有兄弟三人，在齐国和鲁国一带游历，拜了同一位老师学习，学好仁义的道理后回到家。他们的父亲问：‘你们学到的仁义之道是什么样的？’老大说：‘仁义让我爱惜生命而把名声放在其次。’老二说：‘仁义让我可以牺牲生命来成就名声。’老三说：‘仁义让我在保全生命的同时也能名扬天下。’他们三人的见解截然相反，却都出自同一个儒家学派。您说谁是对的，谁是错的呢？”
杨朱回答说：“有一个住在河边的人，熟悉水性，善于游泳，靠划船摆渡赚钱，可以养活上百口人。他的同族人跟他学游泳，结果很多人淹死了。那些人本是去学游泳，而不是去学淹死的，但结果的利害却如此不同。像你刚才说的兄弟三人，到底谁对谁错呢？”心都子听了一声不响地走了出来。
出来后，心都子对孟孙阳说：“羊只有一只，因为岔路太多而丢失了，做学问修道也是，方向太多了，结果失去了真正的学问。学问本来是一个东西，根本也是一个，但分门别类越详细，学问也越没有了，只有追溯到共同的本源、回归到唯一的真理，就不会丧失了。你长期在老师门下，学习老师的学说，却不懂得老师这个比喻的深意，真是可悲啊！”
出自《列子·说符》