Abstract

According to public reason liberalism, the state must abide by a principle of public justification. This principle holds that the laws and institutions of society must be in some sense justifiable to, or acceptable to, all reasonable citizens. But why accept the public justification principle? Recently, Kevin Vallier has developed an interesting and empirically informed argument from social trust to public justification. Sustaining a system of social trust within diverse and large‐scale societies, argues Vallier, requires adherence to the public justification principle. After summarizing Vallier’s argument (Section 1), I argue that Vallier’s defence of public justification does not succeed because there are alternative conceptions of democratic discourse and decision‐making that lack a public justification principle yet that could still sustain social trust (Section 2). I then defend this argument against two objections: that alternatives to public justification would produce less social trust (Section 3) and that such alternatives would not produce social trust in the right way (Section 4).