本文由陸雲的「笑疾」談起，以中國中古時期為範圍，探討醫療傳統對於笑的態度。首先考察醫書中針對笑作為患病的一種症狀如何紀錄、解釋並處治，從而追究醫書作者對笑的理解，最後並試析傳統醫者如何看待喜樂等情緒及其表達。 綜觀自古典醫經到隋唐醫方中對「笑疾」的形容和解釋，可以獲得以下幾點結論。首先，喜笑、善笑與好笑，逐漸變成一種病徵，作為觀察病患的判準和描述之一。其次，對於喜笑不休的治療，有從放血、針灸轉向本草處治的發展軌跡。而當醫書作者以「笑」來形容病患時，指的或是一種快樂的聲音，或是一種牽動臉部的表情。然而不論是情緒昂揚而樂不可支，或是不由自主的身體反應，笑都表現了氣的運轉乃至流失。傳統中國醫學以氣為本的身體觀，對喜怒悲憂恐各種情緒皆不以為然，笑被視為亡精費氣的活動，乃至有「喜則氣緩」之說。而此種諸情不宜，多笑亦無益的養生文化，和現代人主張大笑有益健康形成有趣的對比。

　　　　　This article deals with laughter and the attitudes towards joyful emotions in medical tradition of early imperial China. It first discusses laughing disorders in medical texts and discovers a growing tendency to use laughter as symptoms in description of various disorders, from mental illness, food poisoning, and visceral sickness to demon possession. The treatments suggested for different ailments shifted from bloodletting to acupuncture and moxibustion and later to herbal recipes, much in accord with current knowledge on the development of Chinese medicine. When a doctor used the term “laughter” to describe the patient, he was either trying to capture a kind of human voice that conveyed unbearably joyful emotions or to discern a sort of incontrollable facial expressions and body motions. Either way, according to Chinese medical conceptualization of the body, the patient was suffering from losing his or her essential air, the qi when s/he laughed too much. Since all emotions were considered harmful to one’s health, joy did not occupy a higher status than anger, melancholy, anxiety or fear in the culture of life-nourishment. People would be advised by medical doctors not to laugh at all if possible, much to the amazement of the modern seekers of a healthy life.