在對卡萊爾的研究上，其年輕時所遭遇的「憂傷與改變」為學者們探討其智識與道德發展的關鍵；雷絲路事件是卡萊爾自述其「憂傷與改變」的關鍵事實，因此雷絲路事件深受歷來研究卡萊爾的學者們所重視。本文不附會學者們所慣用的《衣裳哲學》書中「三階段」的說法，不採取「智識與道德發展的」角度，而採用卡萊爾當時的書信所強調的「身體健康」的角度來探討卡萊爾的雷絲路事件。因此，本文著重在討論卡萊爾的「病」，以卡萊爾當時的眾多書信為基礎，卡萊爾的日記、回憶錄、自傳式的小說為輔，來詳細了解卡萊爾病情的出現與發展，及其與雷絲路事件的關係。 在對卡萊爾病情的討論上，由於對於駭伯症(hypochondriasis)歷史的瞭解，我們注意到卡萊爾的「神經疾病」，而認為這是卡萊爾「憂傷」的根源。我們從愛丁堡的求學時期談起，尤其是1814年之後，因為從此年起卡萊爾開始陷入孤獨的泥淖之中。我們先檢視卡萊爾生理的疾病，那就是胃腸病。再經由對前此只知專注在胃腸病的問題而無法真正瞭解卡萊爾的病的探討，來引出卡萊爾病情的關鍵——駭伯症。接著討論卡萊爾所說的「靈魂的疾病」，此病使他「吞噬我自己的心」，陷入煉獄之中，甚至發生瀕臨瘋狂的「神經疾病」。卡萊爾在雷絲路事件中頓悟到只有堅決的對抗，才能脫離神經疾病的魔掌，從此展開一生與神經疾病魔鬼的鬥爭。因此，卡萊爾在雷絲路事件的轉變是其掙脫煉獄、獲得新生的關鍵。

Young Carlyle's "sorrow and conversion" is essential in explaining the process of his intellectual and moral development. According to Carlyle's own proclamation, the Leith Walk incident was the crucial change in this process. Scholars have investigated the process of the so-called three stages, which is based on Sartor Resartus, and focused on the role of Leith Walk incident in it. The approach of this article is not based on Carlyle's intellectual and moral development, but on his "physical" problems (especially nervous disorder), which was emphasized in Carlyle's letters. It tries to analyze various sources, in particular Carlyle's abundant contemporary letters in combination with the records of Carlyle's Notebooks, Reminiscences, and Sartor Resartus, in order to understand the appearance and development of Carlyle's illness and its relation to the Leith Walk incident. After discussing the complete development of Carlyle's illness from both physical and psychological aspects, this article reveals that the basic problem of Carlyle's illness was hypochondriasis, not dyspepsia, which caused the conditions of "eating my own heart" and nervous disorder, and led Carlyle into the miserable situation of purgatory. It was not until the Leith Walk incident that Carlyle really determined to defy the devil of hypochondriasis and began the process of his new-birth.