About open and close
The night blooming Cerius is 'a queen for one night'.

Just for midsummer as night falls the Cerius opens his beautiful flowers.
Just for one night, then closes forever with the first rays of the morning sun.
Chinese have an idiom that refers to very short living things:
Tan Hua Yi Xian.
'Hua' refers to the changing point between open and close.
It's closing time you say? Ah no.
There is no closing without opening, no opening without closing.
"It's closing time.
Closing time, open all the doors and let you out into the world".
Leonard Cohen
Beguinage Diest 1671 Belgium.
My hometown, this is the place were I live.
“Closed garden
Come in my garden, my sister”.
This (spiritual) garden is open and closed at the same time.
In Taoism everything has a beginning and an end.
In Tai Chi Chuan as in life there is an opening and a closing part.

Every part of your Tai Chi form has its opening and its closing part.
Follow the course of Nature. When one door closes, another opens, but
often we look so long at the closed door that we do not see
the one which has been opened for us.
Do you like smelling flowers... inhale through the nose in a natural way.
The mouth (exhale) seems to be open but is not open,
it seems closed but is not closed.

Every single Tai Chi movement has its opening and its closing parts.
We can use a short stick to feel exactly the opening
and the closing parts of the body.

What, when, why?
That’s a Tai Chi study on his on right.
Not so easy to do.
'Hua' refers to the changing point between opening and closing.
'Hua' refers to the empty point between fullness and emptiness.
'Hua' refers to the empty space between Ying and Yang.

Opening and closing the 'kwas' is a very important part of your advanced Tai Chi training.
Real chi power comes from correct opening and closing.
The centre is not moving while opening and closing.
The coccyx is centred and aligned, the spirit (shen) reaches to the top of the head.
Stillness of the body and the spirit leads to flexibility and balance,
Stillness leads to calm and deep respiration,
to deep relaxation.
By separating open and close we come to understand ourselves and our interaction with the whole universe.
Ultimately we come to understand
between the manifest world and Tao, the universal spirit of all things.
These seem to be two, but are one.
The past is closed, the future is completely open.
The moment 'now' is open and closed at the same time.
Tai Chi movements (postures) must be open and closed at the same time.
In the form your mouth should be open and closed at the same time.
Open and close are one, these seem to be two, but are one.
All things are one.
Permissive (open) or restrictive (closed)?
Being open minded is not about accepting information mindlessly.
It's about having information and making the right decisions.
About accepting others, yourself and the world as it is, without prejudice.
Being open minded is about sensitivity.
Open and closed are relative to each other.