@Iammyaspectofus: I did find your earlier post a hard read, but some sleep helped. I still dont think i understand it fully.
Agreed, Rasczaks answer is not what i hoped: "i hope that your practical experience with it has not closed your mind about that"
Rasczak irrationally assumes the current state of things about ownership is how it should be. At least it is not rational in a way i can ascertain. He did not give arguments..
Edit: Well, he(and/or others) did give arguments for that line about what property was, although he did not refer to them. Repeating those arguments would not be a bad thing either. But he did not give arguments for his negative response at all, nor refer to them.

I think force and convincing people that someone ought to own it, would be the two ways of defining ownership.(Edit: as yaaarrrggg said, of course) I would also say, that the second is much preferable, and that the second is based on the earlier reasons for ownership.(Although, i might have missed some points.) However, i would say, that the 'force' manner will often be necessary too. Especially if a community decides on ownership, but individuals, or another community disagree on that. I think though, that a community that shares the idea of who owns what should be as inclusive as possible.

But how to achieve this is a rather hard question. Culture already defines it to an extent; but should it not be backed up by law? It seems to me that there are various ways of doing this. And that the idea of how it should define depends on what the goal of it is.
(Reasons set out below(Edit: I mean previous post) where, in same order: productivity, responsibility(including safety), reward, benefit)
Some people say that freedom encompasses ownership as well, so those would say ownership should be treated as something intrinsic to things. Perhaps the reason would be "because they have it already", one point that i guess i missed in my list earlier. To go by the other reasons, ownership in that vain means that they are allowed them to do whatever they want with it.(Besides other rules of such society, like do no harm.)
They are allowed not to use it for production. Whether they lose it/break it is their own business. Safety is perhaps a reason, but not specifically one.(those other rules about harm) It is not specifically a reward, because according to that view, people may trade as they wish. And although the person may benefit from the ownership, it is not the reason.

Other people(including me) think this freedom is less important then actually allocating the resources. The free market may often be good at the productivity- and responsibility-reason, but i do not think it is particularly good at the reward- and benefit-reason. I see no reason, however why the free market should not be usable for its positive aspects.

For the record, I am not saying there are only these two; just trying to get an idea what is out there. Also, if your opinion is the second a bit, it might mean not everything is owned. Like we might keep fossil and archeological finds under ground for future generations to dig up. Like we keep natural reserves for the sake of the thing it self.(One could argue that as ownership by society, though.)
I agree this happens, but i think that it is also -in a way- necessary. Thing is, it should be called assumption, and be admitted. People tend not to want to make unreasonable assumptions if they know the assumption is there.
I do not know exactly how 'person' is to be defined, perhaps human will do for now? I think it is related to what rights (and duties) different creatures have. But that is a difficult question, and perhaps a dangerous one. Although it is stupid, people have used superficial differences to convince themselves other humans were less worthy of living. It is also a very subjective question, i think.