《庄子·内篇·人间世》
凝寂虚无的心境才是虚弱柔顺而能应待宇宙万物的，只有大道才能汇集于凝寂虚无的心境。虚无空明的心境就叫做 心斋 。 
气也者，虚而待物者也。唯道集虚。虚者，心斋也 
Only the endless void is soft and weak, and can accommodate all things, and only the great Way can gather in the endless void. The empty and clear state of mind is called fasting of the mind.