I've been thinking over the criticism of rich people making money from money and not doing anything to earn it except charging usury. Recall above where I said that there is essentially no "hoarding" in modern economics. That is, there is no substantial amount of financial wealth that is held separate from the economy. When people have money in excess of what they want for current use, they make it available to others through investing it or putting it in savings that earn interest.
(Now this is assuming that the amount of money that the old wealth holders consume in a given year is less than the income that is generated from the loaning and investing of their accumulated wealth. The phrase "living on your principle" refers to what happens when a person or group has consumption spending that exceeds their income, and so are constantly reducing their savings. Any person or group that does that will eventually cease to be wealthy.)
But what happens then?
In theory, a person who starts with a pile of money can make money forever while doing no actual work just by letting others use their money, and getting a return on it. And that is why you see the criticism that money accumulates at the top. But what else is involved there? One criticism, as Narz was bringing up, and I didn't really give him an answer for, is that it is lent out to poorer folk who desperately need the money. And some of that does happen, which sometimes leads those borrowers deeper and deeper into a hole of debt. This, of course, would lead to the Marxist critique of the rich getting ever richer doing no work and just sucking labor dry.
But that's not the whole story. Not all money is lent to the poor at usurious interest rates. In fact, the main place to loan money to is to businesses. And businesses use it to create new real wealth. And that is why when you look at lists of who the richest people in the country are you see more names of "new money" than you do of "old money". And the reason is that the "old money" is being lent to the "new money" and the new money is making a higher profit on it than the old.
So in absolute terms the old money can go on making money forever without any actual work. But in practice the share of the total wealth that old wealth controls falls over time as new wealth overtakes and surpasses it. Now that can be helped along, and high estate taxes help to achieve that. But in the long run a family may remain rich for generation after generation without any actual work taking place, but will fade from prominence because newer fortunes, fortunes that they in part made possible by the loaning of their old money, will eclipse the old.
And this helps explain why people with "old money" are so commonly people who are opposed both to estate taxes, and want to zero out all inflation. That is to protect not just the absolute position of wealth, but the relative position of wealth as well, by restricting the creation of new fortunes that will eclipse the old fortunes. A zero inflation policy will not just reduce the creation of new fortunes, but will raise the incomes of the old fortunes.
It is the creation of these new fortunes out of the savings of these old fortunes that justify the system. And that is why so many of the attacks on old money aren't really justified.