Economists are very good at saying that something cannot go on forever, but not so good at saying when it will stop.

If you asked a sample of Americans "What is the temperature of Mars?" about 8% would say they don't know.

For almost 50 years polls have shown that a large majority of the public believe that the budget should be balanced, and for all that time they have elected office seekers who would not balance it. The public cares about deficits, but doesn't care much.

Whatever may be the distribution of uncertainty among economists, the public only gets to hear from those who have certain opinions.

Trends that can't continue, won't.

If a thing can't go on forever, it will eventually stop.

Things that can't go on forever... don't.