Geoff: "Yes, an individual, apart from society, has the right to punish a criminal, on the basis of the natural law."
Andy: "By this I take it you mean, for example, that a hermit has the right to track down and kill a murderer in the desert."
Not just a hermit in the desert, but an individual who lives in a city, as well. Apart from society meaning, "Not necessarily without the approval of society." Because we all know sometimes society doesn't approve of what is just.
Andy: "However, I am not clear whether you think that this is a freedom (he can do it but he doesn't have to) or a duty (he is obligated to)"
It is a freedom in some cases, and in others, it would seem to be an obligation. You are not obliged to re-acquire your stolen property. You do have a right to it, if you so choose. A violent criminal must be taken out of society, lest he hurt others. Your obligation to punish someone, in these circumstances, is based on the a prudential judgment regarding how much of a risk the criminal is.
Andy: "Furthermore, is there any difference if the muderer committed the crime far, far away verses in the general vicinity of the hermit, versus in the hermits cave; is there any difference if the murdered one is a total stranger versus someone the hermit knows about versus someone the hermit interacts with versus a close friend of the hermit versus a family member of the hermit's; if the attempt to commit the crime equals the crime; and if there is anyway for the criminal to regain his right to life? Does the same hold true for other crimes and how so?"
Morally, an attempt to commit a crime is the same as having committed it. Physically, (which is the only thing a civil law must concern itself with) it is not the same. God will deal with the moral aspect. An individual or collective will deal with the physical threat. If someone poses an actual threat, then he should be incarcerated. Period. Nearly every time they let a violent felon out after 5 or however many years, they go out and rob, rape and kill again. They're obviously still a threat, and therefore should still be in prison. Prison isn't directed primarily to "rehabilitation." Its primary intent is to physically keep dangerous people from committing more violence. If someone rehabilitates after a time, great. But such an instance comes from the grace of God, not merely the prison bars that keep them from hurting other people.
Andy: "I would say (and the law does) that the claim to authority and property rests with the abused unless they act (or fail to act) in such a way as to imply that they do not have the right, so long as that right is naturally transmutable (as property and governments, but not life for instance, are). Thus even if the government seized land for highways or the American War for Independence was illegitimate, the fact that the ones depossed of land have acknowledged the government's claim, and the fact that Britain signed a treaty yielidng the colonies, makes it so."
Yes. Machiavelli said something like this, too. "Might makes right." It sounds like you're saying that a kid bullied at school forfeits his right to his lunch money, so long as he is incapable of resisting or speaking out, for fear of getting the tar beaten out of him.
Just because harm has been done does not mean it is moral to continually inflict new harms.
Geoff: "Parents punish because they have a :natural authority: over their children, AND because they are concerned with the interests of others."
Andy: "You are setting "natural authority" and "interests of others" up as distinct. I thought we said above that authority was the right and duties derived from being charged with the interests of others. If so, parents have a natural authority precisely because they have naturally have the obligation to care for the interests of their children. Thus natural authority (whence they derive their right to punish) is not discinct from their parental concern for the interests of their children. However, parental authority need not be and is not the only type of authority, nor the only type of authority that can punish.
What do you mean by natural authority as distinct from authority?"
Parents have a just claim, based on natural law, to discipline their own children in any reasonable manner they see fit. No one besides the parents, however, has the right to give a moral education to the parents' children. Because the parents, not society or unaffiliated individuals, are liable for the behavior of their children.
In civil society, no one has a claim to order another to eat his vegetables. A parent has this right, because the parent is naturally responsible for the moral and physical well-being of his child, who is not yet a grown, responsible adult. No adult has any natural-law-based authority over another adult, except for punishment of a violation of the life, liberty and property of others. God has authority over all. He created natural law. Man can only request that another man perform a morally good act, but demand that he respect the life, liberty and property of others. The right to demand such a thing flows from natural law.
Natural law says that parents have a right to reasonably rule over their children. Natural law does not say one adult has any "right" to rule another adult without his personal, express consent. This personal, express consent is not present in a democratic society where the majority will is imposed on all, even against the will of the minority.
But following the natural law concerning the life, liberty and property of others is a demand of nature, not merely of civil government. Civil government merely exists to punish infringements of these natural law rights of men. That is all. If any positive effects, such as a reduction of crime, flow from this punishment, extra bonus points. But that is not the reason government exists. A legitimate (read: non-taxation based) government may only punish those who have violated contracts or are an active threat to other people.