He admitted that these occult techniques were not especially desirable or palatable, nor did they have a compelling logic behind them, but, he added, they had proved more effective than he expected, and that is why he included them in his medical text Qian Jin Yi Fang.
在古代醫家十三科的分類中，就有專以符咒治病的「祝由科」。唐代名醫孫思邈也曾不吝千金，向各方士學習禁咒、符印之術，關於這些隱密之法，他覺得說起來都不近人情，也無道理可言，然而按法施行，功效卻又出於意表，因此還是將它們都收錄在醫書《千金翼方》之中。