Wang Huizhi, the third son of the great calligrapher Wang Xizhi of the Eastern Jin Dynasty, was a man of lofty pride who chafed at any restraint and lived with unrestrained abandon. Though he held an official post, he often roamed idly about, neglecting his daily duties at the government office.
Later, he simply resigned from his official post and retreated to Shanyin (modern-day Shaoxing), where he spent his days roaming the mountains and waters, drinking wine and composing poetry—living a life of complete freedom and ease.
One winter, heavy snow fell for days until a clear night when the moon emerged, its light glistening on the white snow like sparkling flowers blooming everywhere, pure and lovely.
Wang Huizhi pushed open the window, saw the snow blanketing everything in pure white, and was utterly delighted. Bursting with excitement, he called for his servants to bring out a table and chair, along with wine and dishes, and sat alone in the courtyard, sipping slowly. He drank, admired the scenery, and recited poetry, dancing with joy.
Suddenly, he felt that this scene and mood would be even more enchanting if accompanied by the gentle sound of a zither. This reminded him of his friend Dai Kui, who was skilled in both playing the zither and painting.
"Hey, why not go see him right away?"
Without a moment's hesitation, Wang Huizhi ordered his servants to prepare the boat and set off through the night, not once considering the considerable distance between his home in Shanyin and Dai Kui's residence in Shanxi.
Moonlight spilled across the river, shimmering on the rippling water. The boat glided swiftly forward, and the scenery along the way was draped in silver. Wang Huizhi gazed at the breathtaking nightscape, feeling as if he had stepped into a fairyland.
"Quick! Quick! Row the boat faster!"
Wang Huizhi urged his servant onward, lamenting that he could not reach Dai Kui sooner to enjoy the beautiful scenery together.
The boat had sailed all night, and at dawn, finally arrived at Shanxi. But Wang Huizhi suddenly ordered the servant to turn back. Puzzled, the servant asked why he wouldn't go ashore to see Dai Kui. With a faint smile, he said:
"I originally came on a sudden whim. Now that the mood is gone, I should naturally return. Why must I see Dai Kui?" The idiom "Coming on a Whim" describes arriving with great enthusiasm.
Source: *Book of Jin*, "Biography of Wang Xizhi"
Meaning of the Idiom: Later, the Chinese idiom "乘兴而来" came to describe arriving with great enthusiasm.