Beautiful poem by Zen teacher Ryokan, from the early 1800’s Japan:
What was right yesterday
Is wrong today
In what is right today,
How do you know it was not wrong yesterday
There is no right or wrong,
No predicting gain or loss.
Unable to change their tune,
Those who are foolish glue down bridges of a lute.
Those who are wise get to the source
But keep wandering about for long.
Only when you are neither wise nor foolish
Can you be called one who has attained the way.
(translated by Kazuaki Tanahashi – from Sky Above, Great Wind)