No closed society can sustain anarchy for prolonged periods of time

Thank you for your response. Although I do have a rebuttal for your argument, I also believe you have misread some of my original rules for anarchist societies - they're actually less strict than you would interpret them to be (giving you actually a little more freedom than you allow yourself). Anarchist societies do not have to meet all of the conditions that you quoted from my opening - they only have to meet the condition of being closed (more on that later) and the condition of not having a government (as defined in my original argument). In order to achieve this I contended that they would have to meet at least one of (not all) the conditions you quoted. Now I will respond to your argument... My first point is that your example is unfortunately invalid under my definition. I argued that no closed societies could sustain anarchy for any prolonged period of time. I'm not sure about your group, but my circle of friends is not a closed society. Although they are in general fairly static, people who are not in my circle of friends can get in (if they really want to) fairly easily and people who are in it can leave if they want to and be generally accepted elsewhere in society. So even if they choose not to, there is always that option, so your circle of friends (unless it somehow manages to prevent people from leaving even if they want to) does not meet the condition of being a closed society. However, your argument does point out a problem with my definition: the definition of a "closed society" is rather too strict (what country with the possible exception of North Korea today could be called a truly closed society? ...but I believe that they too cannot sustain anarchy and that is part of the point I would like to debate), so the definition of "closed society" will be amended (unless you have an objection to the new definition) to be "any society such that it is extremely difficult for a large (greater than 10% or so of the total population of the society) group of people to enter or leave in a short period of time." Thus, although the United States was not a closed society under my first definition, it is now since 10% of the US population = 30 million people, and, if you imagine 30 million people flooding over the border (in either direction) you would have to agree that the logistical problems in making something like that happen would prevent it from happening easily in a short period of time (I know the number of illegal immigrants has reached 20 million or so, but (a) I'm not sure whether that counts people born to illegal parents in the United States and (b) it has taken decades to reach this figure and has been difficult for every single one of them). All of your main points are covered in my argument that a circle of friends is not a closed society (by both the old and new definitions). However, your third point raises an interesting possibility that I feel that I should analyze now. That point is, although falling under the possibility I discussed of a collective informal justice system, unique enough to deserve separate attention. This possibility is that the offended punishes the offender. The problem here is also with the gray areas I described in my original argument - unless the punishment is not a 'crime' when applied outside of the justice system (for example, the death penalty is murder and a fine is robbery if not done within the justice system), the 'offender' may believe that he/she has done nothing wrong and will view the 'punishment' as a crime in and of itself, prompting retaliation (since justice is the job of the offended), which will be viewed as yet another crime by the original 'offended', who will retaliate, etc. etc. resulting in a major feud. As these feuds crop up, society will fracture. The difference with your group of friendsis that if two people get in a major feud, they are free to not be friends anymore, while in my definition of a closed society it's more difficult since one of the two parties must leave the society. Also, natural human ties will ensure that the bad feeling spreads, threatening to create more feuds or intensify existing ones. This scenario is only slightly different than the one I discussed in my original argument, but it might (depending on how you read my characterization of 'collective punishment') not quite fall under it (collective punishment could be anything from a kind of personal trade embargo and collective shunning to society spontaneously extracting physical punishment through some kind of volunteer). In any case, the problem with the system of having the offended punish the offender is identical to the problem with 'collective punishment' in general.