本文主要的目標並非要去評定Habermas或Rawls針對彼此作品說了些什麼，而是要去探討他們各自的理論如何處理宗教在公共論域中的地位和功能這一重要問題。首先，筆者將釐清宗教信念、共同意志與公共理性之間的內在關連性。其次，筆者將闡釋Rawls對宗教或宗教信念的態度的改變，也就是從排斥原則轉向為包容原則。最後，筆者將說明Habermas的方法學無神論，以及他為何宣稱宗教是不可以被解消或替代。

The aim of this article is not so much to assess what Habermas and Rawls said about each other’s work, as to examine how their respective theories deal with the important problem of the place and role of religion in public sphere. First of all, the author will clarify the intrinsic relationship between religious beliefs, the common will and public reason. Secondly, the author will explain the Rawls’s attitude to religion or religious belief change is from exclusion principle to inclusive principle. Finally, the author will illustrate the methodological atheism in Habermas’ view, and why he claimed that religion cannot be eliminated or replaced.