I think this last argument of yours is the perhaps the most convincing, or, potentially convincing tot he most people, but I don’t know that youve put it in a way that the peopl who need to be convinced will be convinced by it.

Puttng it in concrete terms might help.

If you have a flat tax, of say, 20 percent, then the guy making 100 dollars a week sees 20 of those dollars go away in taxes, and has to scrape by on 80 dollars a week. To somebody making 80 dollars a week, 20 dollars is a lot of money. Someone making 1000 dollars a week is going to see 200 of that disappear into taxes, and have to scrape by on 800 dollars a week. To be sure, he’d like to have that 200 dollars, but there is no way that he’s going to miss that 200 dollars as much as the guy making 100 dollars a week misses his 20 dollars. The proportion of your pie taken by taxes with a flat tax is the same for everyone,, but when your pie is very small, every sliver counts, while when your pie is too big for you to really eat it all to begin with, you don’t miss a taken slice nearly as much.

The economic hardship felt by those paying a flat tax is not proportional to income, even though the taxes paid are. As the amount of money you make goes up, relative to the minimum it takes to feed and house yourself, the amount of pain you feel from taking the same proportion of money away goes down. This is, of course what you meant, I think, by, “the marginal utility of money to the wealthy is much smaller; as a fraction of their, uh, total utility…”

But people need it spelled out for them. They slept through high school economics, and that was a lifetime ago anyway for many, and their highschool economics teacher was likely as not a Reagan era Laffer curve, supply side goofball anyway.