 The debate over the constituency of public reason has direct implications regarding public reason’s content. The greater the degree to which the constituency of public reason is idealized, the more we are restricting the content of public reason, that is, the pool of ideas or arguments that could be reasonably endorsed by the members of the relevant constituency. And if the content of public reason is restricted in this way, it may be possible to determine which rules or principles are conclusively publicly justified via philosophical analysis, without recourse to any actual deliberations amongst citizens. Conversely, the less idealized our account of public reason’s constituency, the more the content of public reason will be determined by some actual process of deliberation between agents in the real world, or at least more realistic idealizations of such agents.