What is the relationship among the different books of Rawls: A theory of justice, Political Liberalism and The Law of Peoples? The difference can be explained by Rawls’ motivations in writing the books.
- A Theory of Justice
Anti-utilitarianism :Beleiving that utilitarianism, the dominant view till then, cannot offer the foundation for moral soceity, Rawls aims to offer an alternative, Kantian, contractarian theory of moral society. To Rawls, utilitarian maximaization will not gain the consent (the hallmark of legitimacy for many) of those whose interests must be sacrfied for the maximization scheme.
Hypothetical contract: When placed in the original posititon behind the veil of ignorance, according to Rawls, we will want fairness to all, not maximazation of the good. Our sense of fairness will allows us to arrive at two ideas of justice, which we all will be able to consent to.
Two principles of justices: First, we will try to make sure that the maximal basic rights for all are guaranteed. Then we will move on to the next: Equal opportunity and a just rewarding scheme for the efficient users of talents (Reward them when doing so also helps the least advantaged class.)
- Political Liberalism
Pluralism on the good
Establishing himself as the political philosopher of 20th century, Rawls next goal is to save the liberal society. Rawls believes that a liberal society is inherently unstable since people can form and live by whatever idea of good life they have. I am a Buddhist and you are a Christian. I think your idea of good life is wrong and that the world would be better if there is no Christian view of good life. I, with other Buddhists, could wage a war of religion if winning is a sure thing, but it is not. So i might as well tolerate your religion and go on with my Buddhist life style. Rawls maintains that a liberal society is stable as modus vivendi, never stable for the right (moral) reason.
Epistemic modesty
Rawls preaches epistemic modesty that citizens should realize that they could be wrong on their conceptions of the good life. I could be wrong to think that Nirvana is better than the heaven. Naturally, citizens should not talk about their idea of good life in public, political discourse. To Rawls, not exercising epistemic modesty in the public sphere amounts to treating others like being inferior people. When talking in the political arena, one should focus only on the topics that other people with different ideas of good life can reasonably agree. Epistemic modesty thus entails the separation of the public sphere from the private sphere. One can preach the Buddhist life at home, but not at a city hall.
Overlapping consensus
When we exercise epistemic modesty, and become reasonable in public discourse by way of seeking out the consensus of others, according to Rawls, we will have to appeal to our idea of justice (or fairness) to each other: the good divides us; justice unites us! By means of justice obtained is overlapping consensus. The society with overlapping consensus is characterized by its shared core in justice (public sphere) and liberalism in the good (private sphere). The society is stable for the right reason. Rawls calls this way of saving a liberal society political liberalism.
Comment 1 Regarding the relationship between the two books, Rawls thinks (hopes, expects) that the content of the overlapping consensus is his two principles of justice
Comment 2 Why then didn't he say so explicitly? If Rawls did say explicitly that his principles of justice is the content of overlapping consensus, then he will be criticized for not exercising epistemic modesty. Rawls began Political Liberalism with the proclamation that all theories of the good life is a comprehensive doctrine, even his own theory of justice, since it is based on the Kantian conception of good life. That is, by his own admission, his is as a comprehensive doctrine as a utilitarian one.
- The Law of Peoples
The book is Rawls’ attempt at global justice. The question he raises is how a liberal society can coexist with many other forms of societies (nations). Rawls begins with ranking them by acceptability, and declares that some societies, although illiberal, are still OK. He calls such OK societies the decent hierarchical societies. These societies are characterized by a state religion (a comprehensive doctrine: thus not founded on political liberalism). The decent societies however treat their people well as they protect their basic rights (to a degree) and provide public goods. Rawls thinks that the perpetual peace, hoped by Kant, is possible when (political) liberal societies cooperate with the decent societies.