胸有成竹 — “Have bamboo in one's chest/mind”

Wen Tong, also known as Yu Ke, was a renowned painter of bamboo during the Northern Song Dynasty. People from far and wide sought his paintings daily. What was the secret to his remarkable skill?

Wen Tong had planted various types of bamboo around his house. Regardless of spring or winter, sun or rain, he would frequently visit the bamboo grove to observe their growth and changes, studying the length and thickness of the branches, and the shape and color of the leaves. Whenever he gained a new insight, he would return to his study, prepare his paper and ink, and paint the impressions he had formed in his mind.

Over time, the images of bamboo in different seasons, weather, and times of day were deeply etched into his heart. When he picked up his brush and stood before the paper, all the forms of bamboo he had observed would immediately appear before his eyes. Thus, every time he painted bamboo, he appeared calm and self-assured, and his paintings were always vivid and lifelike. When people praised his work, he would humbly say, "I just paint the bamboo that has matured in my mind."

A young man, wishing to learn bamboo painting, heard that the poet Chao Buzhi had a deep understanding of Wen Tong's art and sought his guidance. Chao Buzhi wrote a poem for him, which included the lines: "Yu Ke paints bamboo, with complete bamboo in his chest." This story originates from Su Shi's "Record of Wen Yu Ke's Yun Dang Valley Leaning Bamboos" from the Northern Song Dynasty.

"胸有成竹" (xiōng yǒu chéng zhú) now describes being fully prepared before an undertaking, having great confidence in its success, and remaining calm and composed when facing situations.