During the Eastern Jin Dynasty, there lived a renowned calligrapher named Wang Xizhi, styled Yishao, a native of Langya Linyi (present-day Shandong).
By the age of seven, Wang Xizhi was already showing remarkable talent, writing beautifully. At twelve, he stumbled upon a book on calligraphy hidden in his father's pillow and secretly read it. When his father discovered this, he demanded, 'This is a treasured book I've kept specially—why did you take it without permission?'
In truth, his father was not unwilling to let Wang Xizhi see the book, but feared that in his youthful ignorance he might divulge its contents, so he told him, "Do not rush; once you have grown into a man, I will pass it on to you." Already captivated by the book, Wang Xizhi pleaded repeatedly, "If I cannot grasp its wisdom now, what use will it be when I am older?"
Impressed by his reasoning, Wang Xizhi's father immediately gave him the book. Wang Xizhi treasured it like a priceless gem, studying day and night with unwavering focus, reaching a state of complete absorption. Following the book's methods for brushwork, within less than a month, the results were immediate—his calligraphy improved dramatically.
At that time, the renowned female calligrapher Lady Wei saw Wang Xizhi's characters and exclaimed, "This child must have seen some secret technique for using the brush. I have seen his writing, and it feels exceptionally vigorous and mature. In the future, his reputation will surely surpass mine."
As Wang Xizhi grew older, he diligently studied the works of past masters Zhang Zhi and Zhong Yao, learning from their strengths to develop his own unique style. He once remarked to others, "The 'Grass Sage' Zhang Zhi practiced calligraphy by the pond until the water turned black. If others could be as dedicated, they would not fall behind him."
As time passed, Wang Xizhi's calligraphy grew ever more refined, and his fame swelled. Many people considered it a great honor to own even a single stroke of his brush.
Throughout history, whenever a remarkable figure achieved fame, people loved to attach strange and fantastical tales to them, and Wang Xizhi was no exception.
It is said that once, when the imperial court was preparing a grand sacrificial ceremony, the calligrapher Wang Xizhi was asked to write the prayer text on a wooden tablet. Later, when the prayer needed revisions, the workers tried to scrape away his original writing.
To their astonishment, the craftsmen examined the prayer tablet and found every stroke of each character had sunk into the wood a full three fen deep, as if carved by a knife, leaving them marveling and heaping praise without end.
Later, people used the idiom "Entering the Wood by Three-Tenths of an Inch" to describe profound insights or penetrating discussions.
Source: Zhang Huaiguan (Tang Dynasty), *Shu Duan*, Chapter "Wang Xizhi"
Meaning of the Idiom: Later, the Chinese idiom "入木三分" came to describe profound insights or penetrating discussions.