狼子野心 — “Refers to a person who is inherently cruel”

During the Spring and Autumn period, two brothers, Ziwen and Ziliang, served as officials in the state of Chu. Ziwen was the Lingyin (prime minister), and Ziliang was the Sima (minister of defense). Ziwen had a son named Ziyang, and Ziliang also had a son named Ziyue.

When Ziyue was born, Ziwen said to Ziliang: 'This child is as strong as a tiger or a bear from the mountains, yet his cries are like a jackal's howl. Although he is very young now, a wolf cub, no matter how small, still possesses a fierce nature and great ambition. I fear he will not be a gentle person when he grows up. I see Ziyue as a wolf, and we must be ruthless and kill him, otherwise, I worry that our family will suffer harm because of him.' However, what parent could bear to kill their own child? Thus, Ziliang absolutely refused to kill his son.

Ziwen, seeing that Ziliang would not heed his advice, told his household: 'If Ziyue ever becomes a high-ranking official, you must leave the state of Chu as early as possible, or disaster will strike.'

After Ziwen's death, his son Ziyang inherited the position of Lingyin, and Ziyue also became Sima. Ziyang did not follow his father's warning and continued to serve as an official in Chu. As soon as Ziyue gained a high office, his political ambitions were exposed. He resented Ziyang's higher position, so he secretly sent Su Jia to kill Ziyang and became Lingyin himself. Not long after, he also killed Su Jia.

Later, Ziyue's ambition grew even larger, and he even wanted to rebel and become the ruler. He then led his troops in a revolt. However, he not only failed but was defeated by a large army sent by the King of Chu, and his family was also implicated. At this time, the family members realized that Ziyue indeed had 'the heart of a wolf and wild ambitions,' and deeply regretted not having listened to Ziwen's advice.