Smart capable personal assistants can be very useful. You give them vague and inconsistent instructions, and they “do what I mean” (DWIM), fixing your mistakes. If you empower them to control your interactions, you need less fear mistakes messing up your interactions.
But one thing a DWIM personal assistant can’t help you so much with is your choice of assistants. If assistants were empowered to use DWIM on your choice to fire them, they might tend to decide you didn’t really mean to fire them. So if you are to have an effective choice of assistants, and thus effective competition among potential assistants, then those same assistants can’t protect you much from possible mistakes in your meta-choices regarding assistants. They can protect you from other choices, but not that choice.
The same applies to letting people choose what city or nation to live in. When people live in a nation then that national government can use regulation to protect them from making many mistakes. For example, it can limit their legally available options of products, services, and contracts. But if people are to have an effective choice to change governments by changing regions, then such governments can’t use regulation much to protect people from mistakes regarding region choice. After all, a government authorized to declare your plan to move away from it to be a mistake can stop you from rejecting it.
Similarly we can elect politicians who pass laws to protect us from many mistakes. But if we are to have an effective choice of politicians to represent us, then they can’t protect us much from bad choices of politicians to represent us. We can’t let our current elected leaders much regulate who we can elect to replace them, if we are to be able to actually replace them.
I’ve long been intrigued by the idea of private law, wherein people can stay in the same place but contract with different legal systems, which then set the rules regarding their legal interactions with others. Such rules might in effect change the laws of tort, crime, marriage, etc. that people live under. And so such competition between private laws might push the law to evolve toward more efficient laws.
One of the things that legal systems tend to do is to protect people from mistakes. For example, contract law won’t enforce contracts it sees as mistakes, and it fills in contract holes it sees resulting from laziness. Law is often DWIM law. Which can be great when you trust your law to choose well. But if one is to have an effective choice of private law, and real competition for that role, then one’s current law shouldn’t be able to overrule one’s choice of a new law. Instead, one’s choice of a private legal system, like one’s choice of nation, needs to be a simple clear choice where one is not much protected from mistakes.
Today we don’t in fact have such private law, because our standard legal system won’t enforce contracts we sign that declare our intent to use different legal systems. To achieve private law, we’d need to change this key feature of our standard legal system.
Your choice to change nations, either for temporary travel or for permanent moves, can be a big mistake. It might result from temporary mood fluctuations, or from misunderstandings about the old nation or the new. Nevertheless we have little regulation of such choices. Instead individuals are mostly fully exposes to their possible mistakes. For example, while Europe is heavily regulated in general, European teens today can decide to go join ISIS, even when many others greatly regret such choices. We disapprove of nations that prevent people from leaving because that cuts competition between nations to serve people.
Similarly, if we want completion between legal systems without forcing people to move, we’ll have to change our law to accept our not protecting people from bad choices of legal systems. There will have to be a simple clear act by which one chooses a law, a choice not much subject to legal review and reversal. We’d want to encourage people to take such choices seriously, but then to accept the choices they make. Freedom of choice requires a freedom to make mistakes. For big choices, those can be big mistakes.
In addition to arbitration agreements (already mentioned) another example (albeit rudimentary) of private law in practice are covenants in homeowners' associations. But Robin, I take your point that these are nowhere near the scope of what you have in mind when you say "private law"
Individuals don't need law which is almost entirely interpersonal.