The mind remains undetermined in the great Void. Here the highest knowledge is unbounded. That which gives things their thusness cannot be delimited by things. So when we speak of 'limits', we remain confined to limited things. The limit of the unlimited is called 'fullness.' The limitlessness of the limited is called 'emptiness.' Tao is the source of both. But it is itself neither fullness nor emptiness
ZhuangziThe true man of the past waited upon Heaven when dealing with people and did not wait upon people when dealing with Heaven.
ZhuangziThere are no greater adversaries than yin and yang, because nothing in Heaven or on Earth escapes them. But it is not yin and yang that do this, it is your heart that makes it so.
Zhuangzi