《魏书·列传·卷二十一》
李预服用了一年，说有效验，但是社交应酬和寝食没有限制，又加之好酒损伤神志，到病重时，对妻儿说： 服用玉屑独居山林，抛弃嗜欲，或许将大大获得神力，但是我酒色不断，是自己走向死亡，不是仙丹的过错。
预服经年，云有效验，而世事寝食不禁节，又加之好酒损志，及疾笃，谓妻子曰： 服玉屏居山林，排弃嗜欲，或当大有神力，而吾酒色不绝，自致于死，非药过也。
Li Yu consumed the jade for a year, believing it to be beneficial. However, he placed no restrictions on his social interactions, eating, and drinking. This, coupled with the fact that his heavy drinking damaged his mind, meant that by the time he fell deathly ill he told his wife and children: “If one were to consume powdered jade and live alone in the mountains, forsaking all desire, then one might indeed achieve great spiritual power, but since I have continued to indulge in wine and women, this death is my own doing and no fault of the elixir.”