Duke Huan was reading a book in the hall. Wheelwright Pian, who had been chiseling a wheel in the courtyard below, set down his tools and climbed the stairs to ask Duke Huan: "May I ask what words are in the book Your Grace is reading?"
"The classic of a famous sage," the Duke responded.
"Is he still alive?"
"Oh no, he is long dead."
"Then you've been reading the dregs left over by a dead man, isn't it?"
Duke Huan said "How dare a wheelwright to have opinions about the book I read! If you can explain yourself, I'll let it pass. Otherwise, it's death!"
Wheelwright Pian said "In my case I see things in terms of my own work. I chisel at a wheel. If I go too slow, the chisel slides and does not stay put. If I hurry, it jams and doesn't move properly. When it is just right, I can feel it in my hand and respond to it from my heart."
"I can explain this to my son, but I cannot pass on the skills to him. That is why at seventy years old, I am still making wheels. The sage who couldn't pass down his wisdom is already dead; and that's why I say the book you're reading is merely the dregs of a dead man."
~Chuang Tsu, Zhuangzi