Sam makes a good point about violence: It's costly, and ruins your rep. This would cause most sane people to avoid it, and well... shall we say... weeds out the less sane?
But again, ignoring the guns, if someone refuses to abide by (or even show up at) an arbitration, all the injured party need do is make that fact public. Smart, sane people would then avoid dealings with them, for the simple reason that if the guy screwed one person over, they're likely to do it again. So, someone who repeatedly refused or failed to make good on arbitration would rapidly find themselves out in the cold, with no friends, and no business contacts.
Sunny: We're just not seeing it. It all sounds like...sorry, but a bunch of handwaving. By which we mean ad hoc contingency schemes rather than a coherent organized system.
Even with ZAP in place, we don't see how violence is prevented, except that everyone is armed (so everyone is too scared to cause violence). It still sounds like everyone hopes that everyone else will obey the rules. True, in every society the people tacitly agree to cooperate for the good of the whole, but anarchy seems to suggest a certain naivete that ZAP and a free market and unrestricted gun ownership will prevent violence. Other societies however accept that violence will occur and make contingencies for it, whether or not that means forming a government. Granted, characters in EFT acknowledge that Belt society is not perfect, but the comic itself presents the Belt as utopic, with the (rare) internal problem being "magically" solved by a market solution. It all has an unreal feel that we found jarring; we just couldn't suspend our disbelief.
Anywho, the scenario we presented of the gorilloids was meant to allow us try to understand how anarchy would prevent violence but also deal with it if it came up, but the explanations don't sound realistic. It's easy to accept that people willing to cooperate would accept the results of arbitration and be kept in line by the consequences of a breach of contract, but what about a bad person seeking power? Such people don't care about reputation; they aren't intimidated by the shunning techniques you've described. A BPSP could get around attempts to cut him off financially; he could deal with an armed population by securing more powerful arms (unrestricted ownership after all) and a gang to back him up. Once he has a power base he can begin intimidating the weaker members of the community. It becomes worse if he receives support from merchants or manufacturers hoping to cash in on his rise to power, or a significant percentage of the population, either out of fear or greed. Eventually one of two things is going to happen: either the remaining members of the community will violently confront the BPSP before he becomes too powerful, or he will take over the community.
An armed society obviously helps, but ultimately it requires the people in the society in general to do their part to maintain a civil society. You think shunning wouldn't work? It won't if people don't want to support a civil society, but it will if people don't want to have a paranoid, evil, corrupt society.
So you have some guy who either won't submit to arbitration or doesn't agree with the results of arbitration, and he wants to go around and do bad things. First of all is the "armed society" bit. He's refused civil society, and is branded an outlaw. Anybody can kill him without legal consequence, and if there is a reward for doing so, then he'll have bounty hunters after him. More importantly, anyone willingly associating with him will run the risk of ruining
their reputation. So he runs into trouble because he can't find a restaurant that will serve him, a hotel that will let him stay there, a grocery store that will sell him food, or even a retail store that will sell him clothes, medicine, batteries, or other supplies. In any fairly modern technological society, he's going to be denied most of the benefits of living in such a society, unless he gives up and submits to the legal system and the decision of the arbitration.
Yes, I suppose he might be able to live out in the wilds somewhere, assuming he actually can manage to live off the land, and assuming there are some wilds to live in, but he's still a branded outlaw and at risk of capture or being killed.
You think he'll just spend a lot of money and bribe his way? Only if his criminal activity has managed to net a lot of money, and that money isn't traceable. With free banking, there would be multiple currencies, and depending upon his crime, and which currency he had stolen, it might very well be traceable, and merchants could be on the lookout for the specific money he stole.
Otherwise, he's not likely to have a lot of money, and couldn't afford to bribe his way very far. If his crime was murder instead of robbery, for example, why would he have a lot of money?
And don't get started on eccentric millionaires--without government subsidies, contracts, and other government intervention, you'll find that the wealthy in a free society primarily get wealthy by serving their customers and clients better than their competition. A lifetime of building wealth that way instills habits in a human being that are not easily changed or broken, short of outright insanity or dementia developing. And even if our eccentric millionaire did suddenly change after decades of serving people, he would find it hard to continue making more money, and would start losing money, instead, thus providing limits on how far he can keep going with his diminishing supply of money.
In short, human nature would not change, but in an anarchic society, the incentives that people have would be different than they are now. And that would make all the difference in the kind of society we would have.