Objection #1. Although Rawls meant to provide his theory of justice as an alternative to utilitarianism, we can construct a utilitarian theory of justice by changing Rawls' views slightly. Harsyani thinks that we should "go behind a veil of ignorance" and that once we are, we would agree to a principle of utility: maximizing pleasures and minimizing pains over the whole group. Harsyani says that this is like a gamble, where we can end up being anyone in society. Because we want to maximize net pleasures and because we could end up being anyone, Harsyani thinks that we would choose utilitarian principles.
Reply. While this slight change to Rawls' view is a version of utilitarianism, Rawls thinks that the argument is inadequate. First, Harsyani is wrong to describe this as a gamble. When you gamble, there are specific probabilities at work. But this is not like society. Although I know the exact odds of getting four of a kind in poker, there is no way to know the odds that I will end up broke-ass poor from a future financial crisis. It is inaccurate to consider this as a gamble. Second, when the stakes are so high, the rational thing will not be to make a gamble or to maximize pleasures. The rational thing to do will be to avoid uncertainty. Rawls thinks that this is why we will prefer his own theory of justice over a utilitarian position.
Objection #2. Nozick puts forward a theory called Libertarianism (not the same kind of libertarianism on the debate on moral responsibility). This it the view that a just society means a minimal government that respects "natural rights". What rights do we have outside of a society? Nozick thinks that first and foremost, we own ourselvses. Because we own ourselves, we have rights to acquire property by "mixing our labor" with resources. For example, if I go out berry picking and harvest a bunch of berries, I own those berries because I worked to get those berries. Natural property rights forbid social regulation and distribution of goods. We also have a right to buy or sell or trade goods voluntarily. Only voluntary transfers are allowed. Taxation is a theft because it is not a voluntary transfer of our goods. We also have a right to be compensated for violations of our rights to acquire and transfer goods. There are no other rights.
Reply. Libertarianism allows for injustice in a number of areas. First, exploitation is totally legit as long as we are exploited voluntarily. For example, people really need to heat their homes in Minnesota in the winter. If power companies wanted to, they could overcharge for electricity that we use to heat our homes. Natural gas companies can also exploit cold citizens of Minnesota as well. As long as the transfers are voluntary, they are allowed by a libertarian system. Second, there can be people in absolute poverty who we owe nothing to. There is no duty to by charitable to people in need. It would be totally OK in Nozick's system if large groups of people lived in the streets. Third, there can be large relative inequalities. Fourth, there can be environmental degradation. It is not an issue of social justice for Nozick if the environment is ruined so long as everyone has property rights and rights to voluntary transfers of goods. Another reply is to say that according to Nozick's argument, even a very small government cannot be justified. Any government requires money to go to public services. Because any government needs public money, there will be involuntary transfer of money from individuals to the government.