《庄子·内篇·养生主》
我顺着牛身天然的生理结构，把刀劈进筋骨相连的大缝隙，再在骨节的空隙处引刀而入，刀刀顺着牛体本来的结构去；牛体中经络筋骨纠结的容易碍刀的地方，我的刀都绕开走而从未碰到过，何况那些巨大的牛骨头呢！
依乎天理，批大郤，导大窾，因其固然。技经肯綮之未尝，而况大軱乎！
I followed the natural physiological structure of the cow's body, and I cut my knife into the big gap where the tendons and bones were connected, and then introduced the knife into the gap of the joint, and the knife followed the original structure of the cow's body; In the parts of the cow's body where the meridians, tendons and bones are easily entangled and get in the way of the knife, my knife goes around and never touches them, not to mention those huge cow bones!