理性與互惠是審議式民主的核心價值，如何展現於地方治理的過程中，不僅影響到公共審議討論的品質，也是審議式民主落實與否最重要的指標，過去文獻對於這兩個概念主要聚焦於抽象層次的規範性探討。本文以William Dunn（1994）所發展出來的政策論證架構，並以內容分析法分析二○○五年宜蘭社區大學所舉辦的公民會議參與者的發言內容，以及共識結論報告，探索公民在審議過程中的說理過程。研究發現參與者能夠針對其所偏好的政策選項提出主張，進行論證和說理。在正反雙方交詰過程中，企圖尋求支持。不同立場的成員也會依循發話者的類型而轉換，形成一種理性溝通的循環，此種過程體現審議式民主的理性精神。更進一步就參與者的議題立場與會議整體的結論報告交叉分析發現，此種論證能夠透過溝通過程的相互主觀和同理，為公共問題尋求大家都可以接受的理由，跳脫個人偏狹的私利彼此分享合理的論述，進而找到共善的價值，形成共識結論。以上的結果顯示，在嚴謹的結構條件下，審議式民主的核心理念「理性」和「互惠」的價值，得以實踐。同時，在嚴謹的審議條件下，公民的素養與能力也在進行說理、跳脫自利的自我轉型、並且獲致共善結論的過程中展現。這些結果對審議式民主本身價值以及其在台灣地方治理過程的應用與發展而言，是正面而樂觀的。

How core values of deliberative democracy--reason and reciprocity-- are substantiated in local governance process is closely concerned with quality of discussion and has crucial meaning for the vitality of deliberative democracy. Previous literature, however, mostly focused on normal discussion of these values. To fill this void, this article empirically explores the dynamics of public deliberation and examines how deliberative democracy is practiced. Based on William Dunn’s policy argument framework this study analyzes the content of discussions and conclusion report of a consensus conference held in Yi-lan County regarding whether to build science parks locally. This study finds that participants are capable of proposing claims based on their preferences and engaging in reasoning and persuasion. Reasoning styles of participants with different view points change following different dynamics. This transformation facilitates a virtuous cycle of rational communication. Further, our crossexamination of participants’ policy position and final conclusion reports reveals that inter-subjectivity created through deliberation generates commonly accepted reasons and consensus which overpass personal interest. These findings suggest that core values of deliberative democracy are able to be substantiated under strict structural conditions. Under such conditions, participants also demonstrate citizen competence and experience selftransformation through reasoning and reaching consensus. These results provide positive implications for deliberative democracy itself and for its application to Taiwan’s local governance.