一薰一莸

春秋时期，晋献公娶了六个妻子，她们钩心斗角都想当正式夫人立自己所生的儿子为太子。晋献公听信骊姬的花言巧语，要立她为夫人，特地算卦求签，得“一薰一莸，十年尚犹有臭。”结果他逼死申生，逼走重耳、夷吾，闹得国内大乱。

Lavender: vanilla, a metaphor for goodness; Stinky grass is a metaphor for evil things. When the lavender is mixed together, you can only smell the smell but not the fragrance. Metaphor: good is often covered by evil.