This is allegedly a "Zen proverb":
“To be calm is the highest achievement of the self”
I tried to look for it by searching on Google, but I could not find the original. What is the original text of this translated quote?
To be calm is the highest achievement of the self.---Yogi Bhajan.
Note that based on Wikipedia
'Yogi Bhajan was born on August 26, 1929 into a Sikh family in Kot Harkarn, Gujranwala district, in the province of Punjab (now in Pakistan)'.
Firstly, he is not Chinese, also he don't speak Chinese, the original text certainly not in Chinese.