Zhuangzi 莊子 chapter 20 (Shan Mu 山木) excerpt (opening passage)
Translated by Burton Watson p. 209-10 (slight modification) (Cf. Ziporyn p. 84, Mair p. 185-6. This story also appears in the Lüshi Chunqiu 14.8)
“Zhuangzi was walking in the mountains when he saw a huge tree, its branches and leaves thick and lush. A woodcutter paused by its side but made no move to cut it down. When Zhuangzi asked the reason, he replied, “There’s nothing it could be used for!” Zhuangzi said, “Because of its worthlessness (不材), this tree is able to live out the years Heaven gave it (終其天年).”
Down from the mountain, the Master stopped for a night at the house of an old friend. The friend, delighted, ordered his son to kill a goose and prepare it. “One of the geese can cackle and the other can’t,” said the son. “May I ask, please, which I should kill?”
“Kill the one that can’t cackle,” said the host.
The next day Zhuangzi’s disciples questioned him. “Yesterday there was a tree on the mountain that gets to live out the years Heaven gave it because of its worthlessness. Now there’s our host’s goose that gets killed because of its worthlessness. What position (處) would you take in such a case, Master?”
Zhuangzi laughed and said, “I’d probably take a position halfway between worth and worthlessness (材與不材之閒). But halfway between worth and worthlessness, though it might seem to be a good place, really isn’t – you’ll never get away from entanglements there (未免乎累).
It would be very different, though, if you were to climb up on Dao and its De and go drifting and wandering (浮遊), neither praised nor damned (无譽无訾), now a dragon, now a snake, shifting with the times, never willing to hold to one course only. Now up, now down, taking harmony for your measure (以和為量), drifting and wandering with the ancestor of the ten thousand things, treating things as things but not letting them treat you as a thing – then how could you get entangled (累)? This is the rule, the method of Shen Nong and the Yellow Emperor.
“But now, what with the forms of the ten thousand things and the codes of ethics handed down from man to man (人倫之傳), matters don’t proceed in this fashion. Things join only to part, reach completion only to crumble. If sharp-edged, they are blunted; if high-stationed, they are overthrown; if ambitious, they are foiled. Wise, they are schemed against; stupid, they are swindled. What is there, then, that can be counted on? Only one thing, alas! – remember this, my students – only the realm of Dao and its De! (唯道德之鄉)”
This parable works on the assumption that living out one’s natural lifespan (終其天年) is desired/valued. Passing between the extremes of being useful and useless is a fairly good course of action, but avoiding all entanglements can only be achieved by being extremely flexible, elusive and unpredictable and “taking harmony for your measure” (以和為量). Likewise, “avoiding entanglements/attachments” (免乎累) is valued as well.