Tax the rich some more. That recommendation comes from many politicians. It seems obvious

to tax the rich. We tell ourselves they won't miss that little extra bit we take, and

after all, it's only right that they pay their fair share. The technical name for taxing

the rich more is progressivity, and it's hard to oppose a concept that shares its roots

with an optimistic word like progress. But this surface logic obscures some important

truths about progressivity. So let's stand back. The first thing we see when we take our

distance is surprising. It is that many people don't know what progressivity is.

Supposing you pay five dollars in tax on your income. A rich man pays ten dollars because he makes

twice as much as you. This arrangement sounds like progress, right? But that is not a progressive

tax schedule. It is a proportional one, a true fair share. What was once known as the TIE,

but is now commonly called a flat tax. Under a flat tax, everyone pays the same rate no matter

what they earn. In the 1980s, a poll by political scientist Carlin Keene suggested that Americans thought

flat proportional taxes were fair taxes. And as we know from architecture and art, humans are wired

to like proportionality. A progressive tax structure by contrast is actually disproportionate.

Progressivity resembles a flight of stairs. Each individual starts out of the bottom paying the same

rate, say, 10%. When his income rises to a certain line, the taxpayer moves up the step on the

staircase and his rate goes up to say 20%. But only for the share of income passed that line.

And the next step, the rate goes up again, say to 30%. But again, only for the last

share of income. And so on. But the prospect of going up all those stairs tires the climber.

Surveying the rates at the top, workers stop chasing a promotion they once thought they wanted.

Why bother? The taxman will take the money anyhow. When workers or professionals stall on the

stairs, the government loses money. But so do regular people. For when the person who decides

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