一薰一莸 — “One fragrant plant, one foul-smelling plant”

During the Spring and Autumn period, Duke Xian of Jin desired to make Lady Li his consort. He first consulted a tortoise shell oracle, which yielded an inauspicious sign. He then used yarrow stalk divination, which also indicated an unfavorable outcome. Duke Xian, however, insisted, 'I will follow the yarrow stalk divination.'

The diviner countered, 'You must not! The oracle text states: "Your devotion will change, pushing away your former affections; like one fragrant herb and one foul-smelling plant, its stench will still linger after ten years." This meant that Duke Xian, who already had three virtuous sons is the Crown Prince, Chong'er, and Yiwu is would, by favoring Lady Li, abandon his original affections, estrange his beloved sons, and only dote on Lady Li. Such a mixture of good and bad could not lead to peace; even after a decade, the 'stench' (referring to the evil brought by Lady Li) would not dissipate.

Blinded by his love for Lady Li, Duke Xian rejected the diviner's warning and made her his consort.

Later, Lady Li conspired with court officials to make her own son, Xi Qi, the Crown Prince. She plotted against the existing Crown Prince, who, despite fleeing, eventually committed suicide. Chong'er and Yiwu were forced to flee.

After Duke Xian's death, Xi Qi was also assassinated by ministers. The State of Jin endured a decade of political instability, a precise fulfillment of the diviner's prophecy.