Rich’s correspondent has it exactly backwards: Credit is merely the means, real economic growth the end–and the Dow remains the best index of market expectations about the real (as distinct from the financial) economy that we possess. If the Dow were somehow capable of rising 2,000 points in the face of frozen credit markets, in other words, we’d have learned that the economy didn’t need the credit markets as much as we’d supposed (a silly idea, but I’m taking the reader’s own illustration), not that the economy had collapsed.

Of course the credit markets matter. And the Dow may yet sink, badly, as scarce credit cramps real growth. But the Dow’s performance remains a critical–and, so far, a more or less reassuring–datum.