In the song Dynasty (960-1279),there was a scholar whose name was Wen Tong and who styled himself Yuke. He was not only admired by others for his great learning, but also enjoyed widespread renown for his bamboo drawing. Every day there were always quite a few peoply who called at his house to ask for one of his bamboo drawings.
Actually, Wen Tong loved bamboos so much that he had grown various bamboos everywhere around his house. No matter what season it was and no matter whether it was sunny or rainy, he used to go to the bamboo forest to observe how they were growing. He pondered over the lenght and breadth of the bamboo poles as well as the shapes and colours of the leaves. Whenever he had gained a new understanding, he went back to his study, spread a piece of paper and prepareed some ink by rubbing an ink stick on an ink slab, and drew what was in his mind on the paper. Through accumulation over a long period of time, the images of the bamboo in different seasons, under different weather conditions and at different moments were deeply imprinted in his mind.So whenever he stood before the paper and picked up a painting brush with concentrated attention, the various forms of the bamboo which he had observed at ordinary times at once rose before his eyes. And so every time he was drawing bamboos he appeared confident and at ease, and all the bamboos he had painted were very vivid and true to lift.
When people spoke highly of his paintings, he always said modestly that he had just put the images of the bamboo imprinted in his mind on the paper.
A young man wanted to learn bamboo drawing; when he knew that Chao Buzhi had made a profound study of Wen Tong's art of drawing, he went to Chao Buzhi for instruction. Chao Buzhi wrote a poem to him. In the poem, there are the following two lines:
When Yuke was painting the bamboos,
He bad their images ready in his bosom.
Later people have summarized the lines as " having had the images of the bamboo ready in one's bosom," which means having had ready plans or designs in one's mind before doing a certain job so that its success is guaranteed. It is also used go mean being calm and cool - headed in dealing with things.
This story comes from an article writted by Su Shi concerning Wen Yuke's art of bamboo drawing.

北宋畫(huà)家文同，字與可。他畫(huà)的竹子遠(yuǎn)近聞名，每天總有不少人登門(mén)求畫(huà)。文同畫(huà)竹的妙訣在哪里呢？
原來(lái)，文同在自己家的房前屋后種上各種樣的竹子，無(wú)論春夏秋冬，陰睛風(fēng)雨，他經(jīng)常去竹林觀察竹子的生長(zhǎng)變化情況，琢磨竹枝的長(zhǎng)短粗細(xì)，葉子的形態(tài)、顏色，每當(dāng)有新的感受就回到書(shū)房，鋪紙研墨，把心中的印象畫(huà)在紙上。目積月累，竹子在不同季節(jié)、不同天氣、不同時(shí)辰的形象都深深地印在他的心中，只要凝神提筆，在畫(huà)紙前一站，平日觀察到的各種形態(tài)的竹子立刻浮現(xiàn)在眼前。所以每次畫(huà)竹，他都顯得非常從容自信，畫(huà)出的竹子，無(wú)不逼真?zhèn)魃瘛?br> 當(dāng)人們夸獎(jiǎng)他的畫(huà)時(shí)，他總是謙虛地說(shuō)：“我只是把心中琢磨成熟的竹子畫(huà)下來(lái)罷了?！?br> 有位青年想學(xué)畫(huà)竹，得知詩(shī)人晁補(bǔ)之對(duì)文同的畫(huà)很有研究，前往求教?；窝a(bǔ)之寫(xiě)了一首詩(shī)送給他，其中有兩句：“與可畫(huà)竹，胸中有成竹?！?br> “胸有成竹”，比喻做事之前已作好充分準(zhǔn)備，對(duì)事情的成功已有了十分的把握；又比喻遇事不慌，十分沉著。
故事出自北宋蘇軾《文與可yún dāng谷偃竹記》。
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