But it is clearly not for the purpose of resolving cases of this relatively tractable kind that the apparatus of government is invoked, since the essential characteristic distinguishing government from other organizations is that is the ultimate arbiter of the use of force in a geographical territory (see "government" in the Glossary). The express purpose of government in a free society is to provide justice in those very cases where such provision requires the use of force—that is, where parties to disputes are unable to resolve their disagreements by peaceful means, being unable to agree upon a binding arbitrator, for instance. Furthermore, regardless of whether proper restitution is achieved through a limited government or through an anarchist system, those who are compelled to pay for justice (presumably, the aggressors) clearly cannot be called "buyers" in the sense of voluntary purchasers. Indeed, our entire analysis of free-market exchanges (a branch of praxeology known as catallactics) is inapplicable to such situations. For example, the price paid for justice does not relate to any supply schedule based on the subjective value scales of the "buyers." Furthermore, if true justice is to be rendered against the aggressors, then those aggressors, who are the purported "buyers" of justice, cannot in general be permitted to choose freely among the various "sellers," particularly if some of the latter fail to uphold the legitimate interests of victims of aggression. Thus the provision of justice cannot constitute a free market, any more than our system of exchanges of cows for hens (pp. 4.6:1-20) would if the buyers were forced to purchase cows that they might not desire at all, at a price determined by the sellers.