Introduction

One source of controversy surrounding John Rawls's later work — a source of both criticism and praise — has been the impression that he abandoned the philosophical project of figuring out what is truly just, in favour of the political project of working out a feasible consensus for people from a particular political tradition.² One aspect of this controversy is the question of whether Rawls could advance his theory as being worthy of endorsement on the basis of good reasons without also claiming it to be true. In preferring to claim reasonableness rather than truth, [End Page 1] Rawls's main concern seems to have been to distinguish the 'whole truth'³ as represented by a particular comprehensive religious or philosophical doctrine, from the truth about politics given that reasonable people will inevitably disagree about the whole truth. This paper focuses on a second aspect of this controversy: whether a conception of justice that is true or reasonable only given the reasonable pluralism of comprehensive doctrines is still a conception of justice, and not simply a compromise between the contending doctrines. Even if the content of one's conception of justice is formulated independently of the existing range of doctrines, rather than through a process of give-and-take, is not the commitment to adhere to a conception of justice that is political in Rawls's special sense itself a compromise? Rawls denied that political liberalism involved political compromise, in the ordinary sense of an agreement dictated by the balance of forces and dependent on strategic considerations. He insisted that political liberalism was a moral conception, and the underlying ideal of public reason a moral ideal, even if not a comprehensive moral doctrine.⁴ One possibility that has not been explored, however, is that we should construe public reason and related concepts as embodying a form of moral compromise, in the double sense discussed by Martin Benjamin — a principled compromise on issues of moral principle.⁵ Although he did not explicitly consider this possibility, there are indications that Rawls would have rejected the description of public reason as moral compromise. The purpose of this paper, then, is to investigate this non-Rawlsian way of working out one of Rawls's main ideas.

On a first pass, the principle of public reason requires that when we make decisions about public institutions, we not do so on the basis of reasonably contestable views about spiritual, metaphysical, or philosophical questions. As individuals, as members of associations, or as members of religious communities we will continue to live according to [End Page 2] our own views about such questions. But when designing our common institutions, we should agree to consider these matters of deep reasonable controversy irrelevant, not just out of a desire to avoid conflict, but out of respect for each other as free and equal citizens. What is distinctive about public reason, therefore, is that it involves the principled avoidance, bracketing, or tabling of certain disagreements, via the agreement not to use the views in question when making some or all collective decisions.⁶

So described, there is a symmetry involved in the exclusion of non-public reasons that resembles the mutual concessions from the dictionary definition of compromise. Protestants and Catholics agree not to base public decisions on either the Protestant or the Catholic conception of God's will. Theists accept that public institutions and policies should not presuppose nor affirm that God exists, while atheists accept that public institutions and policies should not presuppose nor affirm that God does not exist. Conservatives and liberals agree that public policy should not be based on the beliefs that homosexual conduct is or is not sinful. Such agreements can, of course, be merely prudential, based on strategic considerations, and dependent on the balance of forces. Suppose, however, that in one of these cases each side was willing to adhere to...