Public reason and the availability of truth

In this paper I examine the compatibility of truth and public reason in the process of public justification in John Rawls’s Political Liberalism. I argue against Joshua Cohen’s proposal that a political conception of truth is available for public reason. I conclude that the political conception of truth does not resolve the problem of truthfs exclusion from public reason. To support this I present the following argument: (1) If Cohen’s truth conception resolves the discrepancy between truth and public reason then it is either (a) an internal or (b) an external claim; (2) in either case (a) or (b) Cohenfs political conception of truth is unsatisfactory on its own terms. I provide support for accepting (1) as a plausible interpretation. I argue for (2) by arguing separately that (a) requires further motivation and that (b) violates the Rawlsian constraints required for the political conception of truth. I then suggest possible alternatives for strengthening objectivity that are acceptable to Rawlsians.