are you only arguing about *property* rights? Because you changed my example (relevant to arguments about natural rights, as in a right not to be killed) to one that's relevant to a question about property rights. The kind of individual I was describing won't be able to make anything, so I guess if the topic is limited to property rights then that sort of individual isn't relevant to the argument.
A key point in your argument seems to be that all people (along with potted petunias and, yes, photons) are affected by the same physical forces, such as gravity. That's not what refutes the notion of divine right, but let's stipulate that we agree that there's no god out there granting rights to people, equally or not, so that the notion of the divine right of kings is off the table, and good riddance.
So we have that presidents and paupers, pheasants and photons, are all affected by gravity. Now ... there are a lot of unconnected dots between this uncontroversial claim, and even a limited notion of natural rights pertaining only to property.
From here, trying to follow your argument, you go on to the thought experiment about an island. I don't think that works the way you want it to, but we can come back to it in detail later maybe. In any case a thought experiment like this might help support an argument, but it's not a substitute for an argument.
After that you switch gears entirely and make a *pragmatic* argument against Communism, which I have no problem with at all. But unless you're defining "natural rights" in terms of pragmatism, which wouldn't be a good move, this is an entirely separate kind of argument (but at least it actually is an argument, and a good one IMO from a pragmatic point of view, but just not one that does anything to support the idea of natural rights).
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