《太平广记·卷十八·神仙十八》
一些道学家认为伯丑真正得到了道学中神奥玄妙的真谛，就问他在哪里学的，杨伯丑说： 我在太华山下的金天洞中蒙受伏羲皇帝教我《易经》，还有天地为一的 玄同 大道理，这些深奥的道理，和你们这些世俗的学者们是谈不明白的，你们也不可能理解神仙的道义。 
论者谓其有玄机，因问其所学，曰： 太华之下，金天洞中，我曾受羲皇所教之《易》，与大道 玄同 ，理穷众妙，岂可与世儒常谈，而测神仙之旨乎？ 
Some Taoists believed that Bochou had truly attained the profound truth of esotericism in Taoism, so they asked him where he had studied. Yang Bochou said, "I received the teachings of the "Book of Changes" from Emperor Fuxi in the Jintian Cave under Taihua Mountain, and the profound truth of the unity of heaven and earth. These profound principles cannot be communicated with you worldly scholars, and you cannot understand the morality of immortals."