约翰?罗尔斯(John Rawls，1921-2002)，美国著名哲学家、伦理学家。罗尔斯1921年生于马里兰州的巴尔的摩，1943年毕业于普林斯顿大学，1950年获该校博士学位。先后在普林斯顿大学、康奈尔大学、麻省理工学院和哈佛大学任教。社会正义问题始终是罗尔斯哲学思想的主导性问题。主要著作有： 1971年正式出版的《正义论》，该书被公认为20世纪下半叶西方伦理学和政治哲学领域最重要的理论著作；《政治自由主义》（1993）、《万民法》（1998）、《道德哲学讲演录》（2000）和《作为公平的正义——正义新论》（2001）等。

　　罗尔斯认为稳定性问题是政治哲学需要给予认真对待的一个基本问题，这一问题在他关于政治哲学的思考中占据着越来越重要的地位。正是出于对稳定性问题的关注，罗尔斯在《政治自由主义》一书中系统地提出并阐述了公共理性的观念。罗尔斯考虑的问题是，公民们在理性多元论的条件下如何才能对一种政治正义观念达成一致。由于在现代民主社会当中存在着互不相融但又合乎理性的完备性学说，这些学说中的任何一个都不可能得到所有公民的共同认可，我们也不能期望在不久的将来某一种完备性学说能够被所有的公民一致接受。罗尔斯通过对判断负担的说明认为，人们总会认识到在有关合乎理性的完备性学说方面要达到一种共识是不可能的，尤其是在一个具有宗教差异和哲学差异的社会里要实现和平与和谐的政治目的，这种期望在某个合乎理性的完备性学说上达到一致就更加显得不合实际了。对于罗尔斯来说，立宪政体并不要求人们对某一完备性学说达成一致，他认为社会统一的基础必须以另一种方式来实现，这就是罗尔斯所说的以一种独立于各种完备性学说的方式来建构一种政治正义观念。因此，罗尔斯采取一种建构论的观点来具体规定公平的社会合作条件。这些公平的社会合作条件是那些作为自由和平等的公民代表处在公平地位时，通过他们一致同意的正义原则所给定的，并且强调建构论的基础和前提是隐含在民主社会中公共政治文化的基本理念以及公民共享的实践理性的原则和观念。罗尔斯因此强调他提出的正义原则是一种政治的观点，而不是形而上学的完备性学说。

　　公共理性是民主社会中所有公民共享的政治理性，只有当公民在公共的政治活动中遵循公共理性的要求和限制，才能证明自己政治行动的合法性和正当性。按照罗尔斯的理解，如果每一个公民基于他自身所坚持和信奉的完备性学说能够理解和接受一种政治的正义观念，那么以该政治的正义观念为实质性内容的公共理性就可以成为支撑现代民主社会之稳定性的最合乎理性的基础。更为重要的是，罗尔斯在一种权宜之计和一种重叠共识之间进行了明确的区分。在他看来，当人们认为社会的共识只是建立在自我利益或者群体利益的基础之上，或者只是建立在政治谈判的结果之上时，社会的统一就仅仅是一种表面的现象，社会的稳定性只是偶然的，有赖于不去打破和推翻暂时建立起来的利益平衡。然而，重叠共识则不是一种对接受某些建立在自我利益或群体利益基础上的权威和制度安排的共识，而是所有认可某一政治正义观念的人都从他们自己的完备性观点出发，并且基于其完备性观点所提供的宗教根据、哲学根据和道德根据来引出自己的结论。因此，与一种权宜之计不同，重叠共识所带来的稳定性并不信赖于各种相对力量之间的偶然情形和平衡。这意味着那些认可某一政治正义观念的人不会撤回他们对该政治正义观念的支持，即使各种不同完备性学说之间的相对力量不断地发生变化甚至最终成为决定性的力量的情形也是如此。

　　在寻求怎样才能建立一种可能为所有公民共同认可的观念这一问题上，公民必然面临着由于理性多元论事实的存在所造成的困难和障碍。罗尔斯认为，在这种情况下一种合适的公共讨论方式是，每一个公民在可以合理地期待其他公民也能够认可的政治正义观念的基础上展开对基本政治问题的争论。在公共讨论的过程中，每一个公民都随时准备按照其他同样作为自由和平等的公民可以合理地认可的观点来解释自己的政治行动。公共理性对公民在公共的政治活动中为证明自己行动的正当性所需要的理由进行了限制，这就是公民不能够在公共讨论的过程中通过引证自己所信奉的完备性学说来为自己的政治行动进行辩护。

　　按照罗尔斯对于公共理性的解释，公共理性的主要意味是他所说的公民性责任和民主公民的理想。罗尔斯通过对公共理性的阐述，真正想要表达的东西无非是强调相互性准则在公共的政治对话中所具有的重要性。总之，罗尔斯意义上的公共理性对公共的政治对话中所涉及的议程和论证语言都设置了一定的限制条件，也就是说并不是任何话题和论证语言都可以被允许纳入到公共的政治讨论当中。有待我们进一步思考的问题是，如果一种立宪民主政治不允许生活在其中的人们把他们信以为真的东西带到公共的政治对话中，那么它是否还能够得到人们真诚的支持。

　　Abstract

　　Abstract

　　The problem of stability is the focus of Rawls thoughts about political philosophy, because Rawls think that the problem of stability is fundamental to political philosophy. Rawls present and explicate systematically the conception of public reason in his work Political Liberalism. The main question driving Political Liberalism is that of how it could be possible for citizens to achieve consensus on a single conception of political justice under conditions of reasonable pluralism. Just because there exist all kinds of incompatible yet reasonable comprehensive religious, philosophical, and moral doctrines in a modern democratic society, so no one of these doctrines could be affirmed by all citizens generally. Nor should one expect that in the foreseeable future one of these doctrines, or some other reasonable doctrines, will ever be affirmed by all, or nearly all, citizens. In Rawls opinion, we are to recognize the practical impossibility of reaching reasonable comprehensive doctrines, especially an agreement that might serve the political purpose of achieving peace and concord in a society characterized by religious and philosophical differences. To Rawls, the limited scope of this conclusion is of special importance and he think a constitutional regime does not require an agreement on a comprehensive doctrine: the basis of its social unity lies elsewhere. Rawls adopt, then, a constructivist view to specify the fair terms of social cooperation as given by the principles of justice agreed to by the representatives of free and equal citizens when fairly situated. The bases of this view lie in fundamental ideas of the public political culture as well as citizens shared principles and conceptions of practical reason. So Rawls regard his principles of justice as a political, not a metaphysical conception.

　　Public reason is a shared political reason by all citizens in a modern democratic society. Only when citizens comply with the restriction of public reason in public political activity, can they justify their political actions. Just as Rawls point out, when all citizens understand and accept the political principles of justice from their own comprehensive doctrines, then public reason will become the most reasonable basis for the stability of modern democratic society. More importantly, Rawls make a difference between a modus Vivendi and an overlapping consensus. When we think of social consensus founded on self-or group interests, or on the outcome of political bargaining: social unity is only apparent, as its stability is contingent on circumstances remaining such as not to upset the fortunate convergence of interests. An overlapping consensus, therefore, is not merely a consensus on accepting certain authorities, or on complying with certain institutional arrangements, founded on a convergence of self-or group interests. All those who affirm the political conception start from their own comprehensive view and draw on the religious, philosophical, and moral grounds it provides. This feature of stability highlights a basic contrast between an overlapping consensus and a modus Vivendi, the stability of which does depend on happenstance and a balance of relative forces. This means that those who affirm the various views supporting the political conception will not withdraw their support of it should the relative strength of their view in society increase and eventually become dominant. Individuals will continue to endorse the liberal order regardless of the balance of power among contending comprehensive doctrines. In this way, political stability is possible under conditions of pluralism. Since only a freestanding liberalism can win an overlapping consensus, only a freestanding liberalism can be stable．

　　In these endeavors, too, citizens confront the obstacles to agreement posed by the fact of reasonable pluralism. Hence Rawls proposed a mode of public political discourse in which citizens conduct their fundamental discussions within the framework of what each regards as a political conception of justice based on values that the others can reasonably be expected to endorse. In public political discussion, then, citizens should be ready to explain the basis of their actions to one another in terms each could reasonably expect that others might endorse as consistent with their freedom and equality. This means that, as in political justification generally, citizens are not to appeal to comprehensive religious and philosophical doctrines in properly public discussion.

　　In Rawls interpretation about public reason, public reason mainly means the duty of civility and the ideal of democratic citizenship. What Rawls really want to present is the importance of the standard of reciprocity in public political discourse. In other word, public reason places restrictions on the agenda and the vocabulary of democratic deliberation. The question remains us to think is that any constitutional democracy can sustain conscientious support if it tells its citizens that they cannot rightly say what they believe as part of democratic public dialogue．

　　Key words：public reason; overlapping consensus; the duty of civility; political justification; comprehensive doctrines．