tao teh ching 2

Under heaven all can see beauty as beauty only because there is ugliness.
All can know good as good only because there is evil.

Therefore having and not having arise together.
Difficult and easy complement each other.
Long and short contrast each other;
High and low rest upon each other;
Voice and sound harmoize each other;
Front and back follow each other.

Therefore the sage goes about doing nothing, teaching no-talking [1].
The ten thousand things rise and fall without cease,
Creating, yet not possessing,
Working, yet not taking credit.[2]
Work is done, then forgotten.
Therefore it lasts forever.

[1] All the other translations have the idea of teaching without talking... sans too many splanations.
[2] I like Lau here. He has:

"The myriad creatures rise from it yet it claims no authority;
It gives them life yet claims no possession;
It benefits them yet exacts no gratitude;
It accomplishes its tasks yet lays claim to no merit."

The commentaries all seem fairly straightforward: Things appear. If you're in accord with them, they work out for you; if not, not. What is, is, and is also invariably relative to its opposite. As Alice O. Howell points out, the darkest place in a room is under the lampbase.
However, for all its apparent simplicity, what it seems to me you're being asked to consider is not the idea of relativity and being within the flow, but the actual lived-through fact.
It's all very well, for example, knowing that the medicines named in your prescription will heal you, but unless you buy them and actually take them, this knowledge is of absolutely no use to you, and - in fact - is even wrong. Counting other people's treasure is not of much use to oneself. 'Family treasure does not come in through the front door,' as the Zenrin Kushu says.
What's also important to remember here, and certainly what Grandfather Lao is trying to teach us, is that - in the Taoist world-view (as best expressed by the 'twin-fish' t'ai chi diagram) - opposites literally ARE polar...
You cannot have one without the other. That is the nature of duality.
... And that therefore things are never actually out of balance, no matter how they seem.
When either pole reaches full ascendance, the seed of the other within it is of exactly the same power and so on throughout the cycle of birth, growth, death and dissolution.