Recently Robert B. Talisse has put forth a socio-epistemic justification of liberal democracy that he believes qualifies as a public justification in that it purportedly can be endorsed by all reasonable individuals. In avoiding narrow restraints on reasonableness, Talisse argues that he has in fact proposed a justification that crosses the boundaries of a wide range of religious, philosophical and moral worldviews and in this way the justification is sufficiently pluralistic to overcome the challenges of reasonable pluralism familiar from Rawls. The fascinating argument that Talisse furthers is that when cognitively functional individuals reflect on some of their most basic epistemic commitments they will come to see that, in virtue of these commitments, they are also committed to endorsing key liberal democratic institutions. We argue that the socio-epistemic justification can be reasonably rejected on its own terms and thus fails as a public justification approach. This point is made by illustrating the significance of deep epistemic disagreements in liberal democracies.