社會學之眼存在社會學知識產生之前，或社會學成為一門學科之前，用以察驗與開啟社會學問題意識，挑戰觀者既有認知模式。本論文以法國畫家馬內為例，就其1874年展於沙龍的作品《鐵路》，探討畫家的社會學之眼。馬內是許多社會思想家討論過的對象，但未能將馬內與社會學的發生更緊密關聯。馬內的社會學之眼得透過時代精神論、社會變遷論與社會發生論等角度來理解。本論文主張在反身性的考量下，除用社會學檢視其他領域的姿態來自我檢驗，亦應借取其他領域如藝術領域的經驗，來檢驗社會學自身，以自許作為與時俱進，持續「在形成中」之學科。 This paper utilizes Édouard Manet's work Chemin de fer, also known as Gare Saint Lazare, to discuss the concept of oeil sociologique (sociological eye). Although being selected and exposed in the Salon of 1873, Chemin de fer was very different, in subject, style and even size, from other paintings exposed in the Salon, such as that of Gérôme's Éminence grise. With an oeil sociologique, Manet saw unconsciously and spontaneously ＂problematic＂ dimensions in an ordinary scene. The picture prepares for a good start point of sociological research on railway's impact on modern life. The oeil sociologique is available only when sociological thinking emerges, in a pre-sociological stage prior to consolidation of a discipline called sociology or to initiation of a sociological study. By analyzing Chemin de fer, in accompaniment with Manet's career, I propose that period spirits, social changes and social genetics are potential factors that contribute to the oeil sociologique. Manet's case is a non-reproducible historical experiment occurred in an age when sociology was about to emerge. But the conditions and situations that contribute to Manet's oeil sociologique are heuristic for us in this age of sociology in crisis.