A modern democratic society is characterized not simply by a pluralism of comprehensive religious, philosophical, and moral doctrines but by a pluralism of incompatible yet reasonable comprehensive doctrines. No one of these doctrines is affirmed by citizens generally. Nor should one expect that in the foreseeable future one of them, or some other reasonable doctrine, will ever be affirmed by all, or nearly all, citizens. Political liberalism assumes that, for political purposes, a plurality of reasonable yet incompatible comprehensive doctrines is the normal result of the exercise of human reason within the framework of the free institutions of a constitutional democratic regime. Political liberalism also supposes that a reasonable comprehensive doctrine does not reject the essentials of a democratic regime. (xvi)So, to start, Rawls recognizes that modern society is not based on consensus around the major values or issues; rather, individuals differ in their commitments about rights, justice, and the good human life. How in the context of this pluralism of important value systems, is it possible for a modern society to nonetheless possess the features of civility and stability that we would desire?
Here, then, is what Rawls calls the problem of political liberalism:
How is it possible that there may exist over time a stable and just society of free and equal citizens profoundly divided by reasonable though incompatible religious, philosophical, and moral doctrines? Put another way: How is it possible that deeply opposed though reasonable comprehensive doctrines may live together and all affirm the political conception of a constitutional regime? What is the structure and content of a political conception that can gain the support of such an overlapping consensus? (xviii)One prior thought we may have had about a liberal society is that the state establishes no more than a neutral system of law, within the context of which individuals can pursue their own separate and incompatible conceptions of the right and the good. So the liberal state is a neutral state -- one that gives no privilege to one conception of the good over another.
Neutrality is certainly part of the ideal of a liberal state; but it isn't quite enough. The reason is that some conceptions of the good and the right require the intervention of the state for enforcement. If the Alpha group believe that fetal stem cells are nascent human beings and therefore should never be used for the purpose of scientific research, while the Beta group believe that fetal stem cells are no more than useful compounds of organic molecules that can relieve human misery; then both sides of the debate want to prevail through legislation -- either to prohibit stem cell research or to permit stem cell research. Each side sees its position as being driven by a moral imperative -- and therefore not to be compromised without an unacceptable loss of moral integrity on the part of the losing group.
To overcome this contradiction, neutrality is not enough. We need to add a commitment to democratic, constitutional procedures as being the moral trump card when it comes to legislation about areas of conflict based on fundamental disagreements about the right and the good. Essentially this comes down to a second-order commitment that every citizen needs to share: When policy issues arise that lead to profound disagreement among blocs of citizens, the right solution is the procedurally correct solution arrived at through legitimate democratic processes. In other words, all citizens need to put their commitment to legitimate democratic procedures ahead of their commitment to a particular conception of the good and the right. Democratic values supersede religious, political, and moral convictions when there is no choice but to legislate an issue. Citizens are entitled to argue their case for or against proposed legislation; but they are then morally obligated to accept the democratically chosen outcome as a legitimate resolution of the issue.
Rawls captures this conundrum with the idea of toleration: the idea that citizens must tolerate and respect the strongly-held convictions of their fellow citizens, even while participating in a political process that leads to legislation that is inconsistent with those convictions. This means that if the Alphas prevail through the political process, the Betas need to accept the outcome as morally legitimate -- even though it contradicts their own firmly held moral convictions. But why would one accept the moral necessity of toleration? Doesn't this mean sacrificing one's own moral convictions to the will of a contrary majority? And doesn't this imply that one's own convictions are tentative and conditional?
The answer seems to go along something like these lines. When one is a member of a society, one recognizes the inevitable fact of the kind of fundamental pluralism Rawls has described here. This means that society will sometimes legislate about issues concerning which reasonable citizens disagree, based on fundamental moral convictions on both sides. So the citizen is asked to bracket his/her particular moral convictions when considering outcomes, even as he/she is free to vigorously argue on the basis of those convictions during the process leading up to legislation. The citizen is asked to take a double perspective on his/her own moral convictions: first-person, that these are my convictions and they seem binding and justified from my point of view; and third-person, that there is disagreement about these matters, and the only defensible process for resolving the issue is the democratic process in which each person's reasons count as much as every other person's. This is something like Thomas Nagel's understanding of altruism in The Possibility of Altruism; the individual is asked to recognize the moral reality of other persons and not to assign a privileged role to his/her own perspective.
A key part of Rawls's own solution to this problem of democratic pluralism is the idea of an "overlapping consensus" among citizens. Here is how he defines that idea:
Such a consensus consists of all the reasonable opposing religious, philosophical, and moral doctrines likely to persist over generations and to gain a sizable body of adherents in a more or less just constitutional regime, a regime in which the criterion of justice is that political conception itself. (15)
In such a consensus, the reasonable doctrines endorse the political conception, each from its own point of view. Social unity is based on a consensus on the political conception; and stability is possible when the doctrines making up the consensus are affirmed by society's politically active citizens and the requirements of justice are not too much in conflict with citizens' essential interests as formed and encouraged by their social arrangements. (134)So the ideal here is the notion that some set of constitutional arrangements may be acceptable from all points of view -- from Christian to libertarian to Muslim to socialist. This hope seems to rest on the idea that a neutral, democratic set of political institutions give the best opportunity for the adherents of any particular theory of the good to pursue their interests; so each of the "reasonable opposing religious doctrines" may have good reason to endorse the neutral democratic constitution. (This is a kind of "original position" argument, applied to opposing comprehensive doctrines.)
What makes this a consensus of any kind is not the notion that there is an overlapping set of values that persist across all the comprehensive doctrines; rather, it is the hope that there will be at least one political arrangement that can serve as the consensus choice of all the incompatible comprehensive doctrines.
The preceding account says that the consensus goes down to the fundamental ideas within which justice as fairness is worked out. It supposes agreement deep enough to reach such ideas as those of society as a fair system of cooperation and of citizens as reasonable and rational, and free and equal. As for its breadth, it covers the principles and values of a political conception ... and it applies to the basic structure as a whole. (149)So -- what is a political liberal, according to Rawls? It seems to boil down to this. It is a moral individual who has his/her own conception of the good and set of fundamental doctrines; who recognizes nonetheless that he/she is a member of a polity that is fundamentally plural when it comes to conceptions of the good; who recognizes that there is no basis for insisting on privilege for one's own conception of the good; and who recognizes the moral legitimacy of constitutional democratic procedures when it is necessary to decide among policies that involve conflicting conceptions of the good. It is a person who puts civic commitment to constitutional democratic processes ahead of one's one fundamental convictions when necessary. And it is a person who is fully committed to ensuring the neutrality of the state across fundamental convictions. Neutrality of law across persons and conceptions of the good, full recognition of fundamental pluralism within a modern society, respect for the equal worth of all other citizens, and a recognition that one's own beliefs have no basis for being privileged over those of other citizens -- these are the fundamental commitments of a political liberal.
We can now give a fairly simple explication of illiberal thinking as well. It is moral, religious, or political fundamentalism -- the idea that one's own moral convictions are so compelling that no democratic process could legitimately override them. It is the idea that the individual has a persistent right to oppose the state when the state's actions are inconsistent with one's own moral convictions. It is authoritarian -- it endorses the idea that one's own group or party has the right to override the majority's will when the state contradicts one's fundamental convictions. And it is, of course, a position that is fundamentally disrespectful of democracy and of the equal dignity and worth of one's fellow citizens.