But the manner in which humans interact with each other - the incentives and typical outcomes as they relate to private property - were as true 10,000 years ago as they are today.
I would guess that when we were hunter gatherers, always on the move, it was easier to share what we hunted/gathered than to hoard it. It's difficult to hoard when you're on the move. And it's fun to give. Giving strengthens social bonds too, giving security in the shared generosity of the people you share your life with. Ownership (if it was viewed as ownership) would be restricted to clothes, tools, jewellery, etc. No significant accumulation.
Ownership of one's self and one's labor is not subject to "phases" of history. It's a constant, or at least it ought to be. Certainly some peripheral rules about how we determine property ownership can change, but the fundamental principle that one can and ought to own property which he creates or voluntarily trades for... I don't see that changing until human nature fundamentally changes.
Australian Aborigines, before the Europeans arrived? I'm no expert, but again I'm imagining they lived very close to the earth, trusting the earth and each other to provide food, security, etc, without the need for accumulation.
To be honest, I think those who have a problem with private property are more accurately described as having a problem with "inequality" itself. Seeing two people with different abilities, talents, possessions, opportunities, and lifestyles fundamentally bothers many people. Perhaps it bothers you?
It bothers me that some people have ridiculous amounts of wealth, whilst others are in poverty. This differential in wealth doesn't reflect differentials in ability, effort, etc. Is this acceptable? Is this just? How does it arise?
Yet while humans should be treated equally under a legal system, they are inherently unequal from birth. Some are smarter, some are skilled in a certain area, some are strong and play football well, some make better decisions, some happen upon fortunate circumstances and some make fortune upon their own strength of will. Instead of despising these inequalities, I find them very valuable as they permit a vast division of labor and immense opportunity to cooperate.
Inherently different, not inherently unequal. But sure, all valuable.
We are not ants in a hive... equal in our ambitions, character, and build. Humans are individuals, inherently unequal.
Inherently different, not inherently unequal.
As such, I am highly skeptical of any system which attempts to "communalize" humans.
I'm skeptical of any coercion, including any system which attempts to "individualize" or "selfish-ize" humans.
Humans will always co-operate when it is in their selfish interest to do so (even donating to charity falls into this category typically). But trying to encourage humans to co-operate without strong regard to their own selfishness is a fool's errand, and indeed wholly unnecessary.
I'm not interested in encouraging anything. I'm not interested in characterizing people as selfish or unselfish. I'm interested in imagining, so that it might resonate with like minded/hearted people.
As Adam Smith said, "it is not from the benevolence of the butcher, the baker, or the brewer that we get our dinner." This has been true since the dawn of man, has it not?