Zhang Zhihe or Chang Chih-ho (Chinese: 張志和, fl. 8th century) was a Chinese government official and Taoist scholar.
A native of Zhinhua in Zhejiang, 'he was of a romantic turn of mind and especially fond of Taoist speculations'. He took office under the Emperor Suzung of the Tang dynasty, but got into some trouble and was banished.
Soon after this he shared in a general pardon; whereupon he fled to the woods and mountains and became a wandering recluse, calling himself "the Old Fisherman of the Mists and Waters" (烟波钓叟).
When Lu Yu asked him why he roamed about, Zhang answered and said, "With the empyrean as my home, the bright moon my constant companion, and the Four Seas my inseparable friends, — what mean you by roaming?"
And when a friend offered him a comfortable home instead of his poor boat, he replied, "I prefer to follow the gulls into cloudland, rather than to bury my ethereal self beneath the dust of the world." He was the author of the Yuan Zhen Zi (元真子), a work on the conservation of vitality.
From A Lute of Jade – Being selections from the Classical poets of China [The Wisdom of the East series] edited and translated by L. Cranmer-Byng and Dr S. Kapadia 
A Taoist philosopher who lived in the time of the Emperor Su Tsung, and held office under him. For some offence he was exiled, and the royal pardon found him far too occupied to dream of return.
Like so many of the same philosophy, he became a lonely wanderer, calling himself the "Old Fisherman of the Mists and Waters".
Professor Giles (`Chinese Literature', p. 191) adds the curious statement that "he spent his time in angling, but used no bait, his object not being to catch fish."
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