The second part of the book examines two principles of justice that ought to inform the design of the basic structure. Rawls prefaces the discussion of them with three clarifying points. The first is that these principles are based on the presupposition that they are aiming at the establishment of a democratic society. The second is that justice is the primary concern of such a society. The third point is that his system is designed for a liberal political order, which vests political power in a constitutional system that is ultimately accountable to its citizens. Since citizens within a pluralistic society are permitted to disagree on so many aspects of what they believe and how they live, and since coercing agreement on those matters would be unjust, it is critical for liberalism to establish the principles that are not themselves up for debate. These include the idea of society as a system of fair cooperation and the basic freedom and equality of all citizens. Maintaining such a system requires a specific understanding of justice that establishes the grounds on which citizens must be entirely free and equal and the extent to which a just society can tolerate the inequalities that inevitably develop in social life.