Introduction to Philosophy/Liberalism
The basic liberal-libertarian debate is between John Rawls (the famous advocate of Liberalism) and Robert Nozick (pertaining to Libertarianism). Rawls argues that what should motivate an optimal political society is placing ourselves from the point of view outside that society. In other words, in order to find out what kind of government would be the best, one must ask what one would desire if one did not know what role he/she was going to play in that particular society (Rawls calls this the Veil of Ignorance). From behind this Veil of Ignorance, one should not have any knowledge of any of the particular aspects of the social institutions or distributions in the state. Rawls thinks that given this objective disposition, one would come up with a government whose principles were such that all people in the society would have equal opportunities for everything (and inequalities would be allowed, but only if they maintained to benefit the worst off).
In contrast, Nozick argues against Rawls that, when pertaining to Distributive Justice, one must not take an ahistorical, patterned view of distribution, but rather look at the situation historically. That is, a distribution is just if it satisfies the principles of justice in attainment and of justice in transfer. For Nozick, one can acquire (own) something in two ways: either that thing was previously unowned, and the person acquired it while leaving enough and as good of it left for others, or that thing was transfered to him/her by an act of legitimately freely informed consent on the part of the previous owner. He allows also for some principles of retribution if an act is unjust, and allows here for there to be some orientations of patterned redistribution. However, at base, Nozick's point is that when trying to decide whether an ownership is just, we must decide whether the individual acquired it legitimately, not whether it brings about the greatest overall happiness (read: Utilitarianism) or benefits the worst off.
Thomas Nagel would give a third opinion to try and reconcile these claims by pointing out that the problem in this debate and subsequently in all of political theory is the delicate balancing and often asymmetry between concerns of personal politics (the individual's concerns) and collective politics (the concerns for others). This is a bit of an echoing of Rousseau's theory of the General Will, where he tries to account for individuals acting in one way to support their private, personal desires, and in another way to act according to concerns of the whole. John Stuart Mill also deals with this dichotomy by claiming that societies need to promote the greatest overall happiness for the greatest number of people (his principle of Utilitarianism) while still maintaining that it (the Government) enables the possibility for its citizens to individually pursue the betterment of their own lives.