> ends where mine begins and vice versa

That tipping point isn’t fixed.

> furthermore, does not change over time

Except it does “them’s fighting words” only died out very recently, but it provides a starkly different boundary between my rights and your rights.

Ritualized lethal combat was a thing for very long time, and took an incredibly long time to go away. Trial by combat and dueling grows out of a fundamentally different ethical framework not just a lack of technology. It seems antithetical to Christianity today, but that wasn’t always the case.