As humans we've always had the concept of "property" to some extent, independent of government. That's not true of copyright law. That was something we invented in response to a specific need, but we invented it at a time when few/no other legal or intellectual tools were available. Copyright should never be treated as the sacred cow that property rights in general are, IMO.

This "natural rights" talk sounds like theology to me. From an anthropological perspective, humans invented intellectual property around the time it became useful, just as humans invented land ownership around the time that became useful. You can say the same about owning shares of a business or owning currency. These are exactly the artificial property rights you need for capitalism, and you need government for those rights, and hence capitalism, to actually work.

As does the idea that governments are a magical prerequisite for property rights.

... just as humans invented land ownership around the time that became useful.

Try taking a bone away from a dog, and my point might seem clearer.

What you need for capitalism is centrally enforced rights to things like land and corporate equity. That is not a simple extrapolation for protecting one's personal possessions any more than copyright is. And like copyright, they require a government.

I just finished a Law 101 class so I'm by no means an expert, but I think the above explains the theory behind why we need laws. Whether you think the theory is legitimate or not is up to you. When I started the course, I was surprised to learn that our entire legal system was designed around the concept of property rights.