本文将英国诗人杰弗里?乔叟后期的新现实主义视为中世纪后期奥卡姆唯名论革命的结果，其根源在于奥卡姆对亚里士多德逻辑的唯名论解读。亚里士多德的逻辑体系《工具篇》中，只有演绎逻辑在中世纪欧洲得以保存，并成为中世纪神学、哲学和世界观的基石；直到十二世纪下半叶，亚氏逻辑学全集才被重新发现并翻译回欧洲。基于对亚氏归纳逻辑的创新解读，奥卡姆的唯名论哲学认为只有个体“殊相”是真实存在的，抽象的“共相”只是名相，不具有客观实在性。这从根源上改变了人对世界的认知。本文解读乔叟晚期的重要诗歌作品《特洛伊罗斯与克丽西达》，特别是其描写手法、诗歌语言和情节设定，以探究乔叟如何应用奥卡姆对亚氏逻辑的唯名论解读，用创新的写实主义风格改造了中世纪抽象寓言诗传统。受其影响，乔叟在后期作品中摒弃了寓言体。他通过实践奥卡姆对亚氏逻辑《后分析篇》的理解，将中世纪寓言诗中的抽象人物塑造成具体历史情境中的真实个体，并创新地将“共相”寓于对个体“殊相”的再现。乔叟似乎已敏锐地察觉到，在中世纪晚期奥卡姆唯名论革命的冲击下，抽象寓言诗已无法再现出变换的现实世界，他的后期作品似乎是对抽象寓言诗传统的主动背离。乔叟的新现实主义展现了中世纪-现代范式转换——从中世纪经院哲学关注本质的知识论到唯名论关注个体现象的知识论，从基于普适原则的演绎逻辑到基于实证和观察的归纳逻辑。因而我们可以说，孕育了乔叟新现实主义的唯名论革命同样孕育了现代科学的实证研究方法。

The thesis strives to articulate a better understanding of how Geoffrey Chaucer’s late poetics is grounded in William of Ockham’s Nominalist understanding of Aristotle’s Organon. As we know, only Aristotle’s deductive logic was known in the medieval period. Based on Aristotle’s full logical corpus, especially his inductive logic, recovered in the late twelfth century, Ockham’s Nominalism affirmed the existence of particulars only and regarded universals as merely ‘names’. Aristotle’s full Organon, especially in Ockham’s Nominalist interpretation and understanding, created a revolution in medieval perception and thinking. From what combination of sources it would be difficult to determine, but Chaucer appropriated this understanding in his later poetry. The thesis specifically investigates how Chaucer’s reception and application of Nominalist Aristotelean logic had a profound stylistic and thematic impact on his later poetry. As a case in point, the thesis examines how Chaucer’s apprehension of Aristotle’s new logic manifests itself in his Troilus and Criseyde in the 1380s. It analyzes how Chaucer’s characterizations, use of language and settings appropriate Aristotelean logical approaches, methods and concepts in his reworking of his traditional medieval sources. Early in his career, Chaucer wrote fairly typical allegorical poems, but his poetry, responding to Nominalist trends, changed radically, as can be seen in Troilus and Criseyde and The Canterbury Tales. In these late poems, it can be seen clearly how Chaucer applies the nominalist understanding of Aristotle’s Posterior Analytics to transform medieval abstract allegorical characters into concrete particular people in specific historical settings. Chaucer’s innovation is that he finds a unique way to preserve these abstract universals in his representation of concrete particulars. As the thesis demonstrates, Chaucer consciously departs from the medieval allegorical tradition, which has been rendered futile by the rapidly changing late medieval world. His new poetic style is a more effective means for capturing the changing and fluctuating world brought into being by the Nominalist revolution. Through his concrete new realism, Chaucer’s innovative poetics exemplify the late medieval paradigm shift from Scholastic “scientia” (abstract knowledge of universals based on deductive reasoning from assumed first principles) to Nominalist “historia” (concrete knowledge of particular phenomena based on empirical observation). Finally, Chaucer comes across in these later poems more modern than medieval. His innovative gaze anticipates modern scientific modes of empirical inquiry.