@ OP
Essentially, for mutualists, only private property in a person’s possession is legitimate. Absentee ownership, bank loans, landlording, specialization between capitalist and worker, ect are all illigitmate.
Right. They adhere to a theory of ownership that they call “occupation and use”. However, when pressed on the intended meaning of this phrase, they seem to typically agree that they don’t mean it quite literally. For example, if I leave my car in a parking lot, they’d say that I still own the car, even though I’m not currently occupying or using it in a literal sense. But one can interpret “use” such that one is still using his property when he allows others to use it in his stead. At this point, it’s clear that mutualists simply consider some uses of property (in a broad sense) to be illegitimate. Why would this be? I think it’s because they oppose profit, rent, and interest. That is, I think the “occupation and use” was constructed as a rationalization for this opposition.
So then what’s the real (i.e. original) reason for opposing profit, rent, and interest? From what I can tell, the reason is twofold. First off, it seems that many of the earliest “socialists” were not opposed to profit, rent, and interest per se - they were opposed to such only when it was obtained through what we’d now call aggressive action. Second, many of them also seem to have appealed to some notion of objective value. In that case, profit, rent, and interest were seen as violations of such.
How do you define posession?
That to me is the most blaring flaw of mutualism. The conditions for possession are arbitrary and impossible to define. When one goes out for groceries, does a thief not have a right to your house because you don’t possess it? Or what if your mother gets sick and you have to go visit her for three weeks. Do you forfeit the right to your property? Mutualism might exist in a robotic computer-program version of reality, but not otherwise.