The four:

Voidness and fullness
Softness and hardness
Building up and tearing down
Filling and emptying.

There is none but these,
these are the essence of action
and so are the essence of neutralization

These four are also:

000-111
010-101
001-110
100-011

As that each is a pair we style them as eight
but they are no more eight than they are one
one that is composed to two parts, null and void

These eight energies have a source undifferentiated
it is styled: the Mother of Yin and Yang
But as undifferentiated-ness itself, what name can it bear?
It is all things and so it great
It is without limit and so is ultimate
and so it is styled: Taiji
It is the way of all things
And so it is styled: Tao