Jia Yi was an outstanding statesman and literary figure of the Western Han Dynasty. He was known as a "child prodigy" from a young age, gaining widespread fame by the age of 18. Emperor Wen of Han valued him greatly and appointed him as Grand Tutor to King Liang.

During his tenure, Jia Yi dedicated himself to writing, pouring his talent into his works. His timeless political treatise, "On Public Security" (治安策), was a masterpiece from this period.

In this essay, Jia Yi analyzed the painful lessons of the Qin Dynasty's decline from prosperity to collapse due to corrupt officials and tyrannical rule. He concluded by saying: "The overturned cart in front serves as a warning for the cart behind. The failure of the Qin Dynasty should alert us sufficiently! Otherwise, we too might repeat the Qin's mistakes, which would be too dangerous!"

After reading "On Public Security," Emperor Wen of Han greatly admired Jia Yi and adopted some of the suggestions in the essay.