  This strong orientation toward cognitive validity qualifies Habermas's version of deliberative democracy as an “epistemic” theory. This puts his democratic principle in a rather puzzling position. On the one hand, it represents a specification of the discourse principle for a particular kind of discourse (legal-political discourse). This makes it analogous to the moral principle (U), which specifies (D) for moral discourse. As a specific principle of reasonable discourse, the democratic principle seems to have the character of an idealizing presupposition insofar as it presumes the possibility of consensual decisionmaking in politics. For Habermas, reasonable political discourse must at least begin with the supposition that legal questions admit in principle of single right answers (1996c, 1491–95), or at least a set of discursively valid answers on which a fair compromise, acceptable to all parties, is possible. This highly cognitive, consensualist presumption has drawn fire even from sympathetic commentators. One difficulty lies in Habermas's assumption that in public discourse over controversial political issues, citizens can separate the moral constraints on acceptable solutions, presumably open to general consensus, from ethical-political and pragmatic considerations, over which reasonable citizens may reasonably disagree. As various critics have pointed out, this distinction is very hard to maintain in practice, and perhaps in theory as well (Bohman 1996; McCarthy 1998; Warnke 1999). 