If you were to somehow accumulate all of the wealth in the world and divide it evenly among everybody in the human race ... well, for one thing, most of us would starve, because the act of dividing up that wealth would almost certainly wreck an awful lot of our productive capacity. But even if you found some way to avoid that pitfall, let's face it: by the end of the first week, it would be distributed unevenly, if for no other reason than no cure has ever been found for the urge to gamble. Even if you managed to stifle short-term gambling and managed to educate people completely out of short-term stupidism first, by the end of the first year the amount of wealth people had would vary widely. Two farmers on side-by-side fields planting the same crops with the same equipment in roughly the same soil; one of them's going to have more luck than the other, with rainfall or pests or whatever, and he's going to harvest more crops. That's just as true in every other line of work. Attribute it to luck, attribute it to spirits, attribute it to God or the gods, but not everybody who does the same thing ends up with the same outcome.
So if you want egalitarianism, somebody's going to have to go around and tally up everything that everybody has every year (at least), divide by the number of people, and take away everything above that from the people who have it and give it to the people who have less than that. Now frankly, this is already the point in the conversation at which we've demonstrated that anarchism is deranged: once you have the mandatory power to compel taxation, it's a government, no matter what you call it. But there have always been a handful of anarchists who've insisted that if people weren't somehow traumatized by living under government or taught bad habits by a government, they'd never think to object to giving away all of their excess wealth. This has been tried. Over and over and over again. The net result is that everybody starves. Every time. You can not "educate" a human being to recognize an identical need in his neighbor as just as pressing a need as the same need when he feels it himself. You can not "educate" a human being to recognize that if he and his neighbor are working equally hard, he isn't working harder than that lazy bum over there. You don't have to be on the autism spectrum to fail to recognize other people's identical pain as being as intense as your own; on the contrary, it may actually be easier to teach this to those of us on the autism spectrum, because we rely on harder to spoof cues, like actual facts rather than emotional expressions. Every time "from each according to his abilities to each according to his needs" has been tried, the result has without exception been that people over-state their needs and under-estimate their own abilities, under-estimate everybody else's needs and over-state everybody else's abilities. No exception has ever been recorded, no matter what education (spiritual or practical) went into the population, however carefully selected, before the experiment has been begun.
But okay, let's assume that you have found some hitherto unknown way to do just that, to make everybody agree on what sharing fairly looks like. We are already deep into false-to-fact counterfactual territory here, but to humor the anarchists, let's keep going. After all, the experiment they want us all to undertake has been tried many times, some times have gotten farther than others. What happens next? Without exception in all of recorded history, someone concludes that if people would stop taking away his stuff every year, he could make even more stuff, and next year there'd be a lot more to share. He might even be right, up to a certain point. Or he could be kidding himself, which is going to be true more often. Either way, after a few years of resenting watching his stuff get carted away by the redistributors, it is as sure as the sun coming up in the morning going to occur to him that for less than what was taken from him, he could hire his own armed guards to turn back the redistributors. And now he's a warlord.
But the real problem doesn't even get started until two people think of this. Because maybe he really was right; maybe he could produce a lot more, and he and his warriors live well, and maybe he even stays educated like the anarchists assure us he would and wants to share the same amount with the greater community that the redistributors were taking away from him before. It could happen. I know it could happen; it has happened before. What happens, though, the first time somebody else raises their own private army to guard their stuff? One of the two of them looks over at the other one's private army and goes, "oh, crap, if he wanted to, he could send them over to take away my stuff." So now he has to have a bigger army. Maybe he gets more productive. Probably he does. But the same logic that applied to the two farmers with side-by-side fields applies here: even if he and the other nearby warlord start with equal resources and equal skill, by sheer luck one of them is going to end up richer than the other one. Which means that he can afford the bigger army. So now what does the unlucky warlord do? Now it's a matter of life and death; screw egalitarianism, I've got to get a bigger army. So now by simple logic he has no choice but to go on a war of conquest against any non-warlords he can conquer, and redistribution now goes the other way now: from the poor to the rich, to fund an arms race. History does not yet record a single instance of this experiment being tried where, if it even made it this far, that isn't what happened.
And if we stopped there, the people with Social Dominance Orientation would be right. But they're not. Observe.
During the dark age that followed the crisis of 1200 BCE, modern-day Greece was settled by two different tribes, both of them people who'd deliberately left civilization with an intent to never be ruled again. Within a couple of generations, though, they were already up to their necks in tribal warlords, and most of the population was starving to fund armies to defend the rival warlords from each other. After one particularly ugly spasm of inter-tribal warfare, all of the tribal warlords in the area around Athens agreed to a negotiated settlement. They picked one guy with a reputation for being fair, and swore their most sacred oaths to obey whatever peace treaty he wrote. The man's name was Solon, and he went far, far beyond his mandate, deciding instead to solve the original problem of warlordism. He abused their oaths to make them agree to one more round of really aggressive confiscation and redistribution, in this case of the farmland, along with a total wiping clean of all recorded debt. He then set up several limits by which anybody who got anywhere near amassing enough wealth to be able to afford an army would have it taken away from him before it got that far; he could have more wealth than anybody less hard working and less lucky, right up to that point, but no farther. And he incorporated a set of political and religious monitoring and auditing systems whereby if anybody did try to keep enough wealth to be able to raise an army of his own, everybody else would know it ... and know to descend on him en masse and stop him.
Solon was not given a mandate to redistribute land and wealth as radically as he did. They were bound by their oaths to obey, but they weren't bound by oath not to punish him. Every single wealthy warlord spent money they were about to lose anyway, before the redistributors got there, to hire the best hired killers in the region to track down Solon and kill him. He barely escaped with his life, and fled into exile under an assumed name. But here's the funny thing: seven years later, those same rich people sent out embassies to the whole known world, begging for Solon to come home, because having seen how it worked out, they had to admit that he had been right. Divinely inspired Solon, they called him thereafter, for the next several hundred years. And divinely inspired he may well have been; he was displaying the clear mark of inspiration, someone operating far beyond their own known capabilities. But seven years into this system, the rich people of Athens realized that they had never been as afraid of their own poor people as they were of their fellow wealthy people; that they had squandered so much money on defending themselves from hypothetical or actual threats from their fellow wealthy people that they were living better, more comfortably without the money than they had been when they had it.
Look, one great constant throughout all of history is that rich people arise through inescapable laws of nature. And once they do, there is no way to make them share any of that with us. You will never come up with a system where the people who have more can't find some way to hire guards, bribe judges and priests, impress the public with their short-term generosity, and hire writers and poets and philosophers to convince everybody else that they the rich people are right to insist on keeping all of their stuff. If Plato and Socrates were alive today, they'd be working at the Heritage Foundation and the Cato Institute, doing their flat level best for the same kinds of wealthy people who funded all of the philosophers except Diogenes the Cynic back in the day. (This of course makes Aristophanes the Michael Moore of ancient Athens. Don't think so? Read Clouds, a play that doesn't get staged nearly often enough if you ask me. The famous and hysterically funny debate between Good Logic and Bad Logic lacks only Powerpoint slides of being right out of Roger and Me.) But history has shown, and not just in ancient Athens, that if you persuade the rich that they are better off giving up an awful lot of the stuff they earn or make, as long as all of their fellow rich people have to do so too, then they're all better off, even if all you can appeal to is the logic of negotiated mutual arms reduction.
Think it wouldn't happen here? It has. And does so again every generation. I've already run too long, though. I have a specific example in mind; I'll give it to you tomorrow.