Seemingly dull and delphic words from the Federal Reserve chairman sent investors into raptures yesterday. Stocks, bonds and gold all took flight. And why? Alan Greenspan’s successor dropped a hint that the Fed might stop raising its interest rate, the so-called Federal funds rate.

It is good to remember that an interest rate is a price. The funds rate, specifically, is the price of an overnight loan. And the Fed fixes it. Ben S.Bernanke, the new Mr. Monetary Policy, indicated that the Fed would consider fixing it at a level a little more to the liking of the nation’s borrowers.

Twice a year, the Fed chairman must present himself to the plenum of the House and Senate Banking committees. Sitting before these eminences, he says his piece on monetary policy and listens to them say theirs. Mr. Bernanke bore up manfully under the gale of senatorial palaver. We wish him strength today at the House.

Mr. Bernanke’s anodyne words were just what Wall Street was hoping to hear. Inflation is worrisomely high, said the former Princeton economics professor — but is moderating. Economic growth is strong — but has begun to subside. The red-hot American residential real estate market is cooling — but not crashing.

This is fraught moment in monetary policy. It is a tribulation both for those who make it and for those who, so to speak, consume it. Anyone with a dollar bill in his wallet is a customer of the Federal Reserve. We have no choice.

“Too little, too late; too much too long.” So goes the Wall Street adage about Federal Reserve interest-rate policy. They are words both clever and wise, underscoring as they do the fact that the personnel of the Fed are only human. They are prey to the very errors of calculation and emotion that trap many investors.

The Fed, of course, is not in the investment business. It is in the price-fixing-cum-economic planning line of work, a difficult and hazardous trade. To try to resuscitate the economy after the bursting of the stock-market bubble, the Greenspan Fed pushed the funds rate all the way down to 1%. Not surprisingly, the American people availed themselves of what looked like free mortgage credit. House prices soared. The rate of inflation crept higher.

Now the Consumer Price Index is rising by 4.2% year over year while the encumbered American home owner groans under the weight of rising mortgage interest expense. If you were Mr. Bernanke, would you tighten the screws to stop inflation? (Inflation is a laging indicator, as the economists say, but currency debasement is a sinister and persistent theme in our modern monetary history.) Or would you stand pat, reasoning that the full effect of 17 consecutive tightening moves won’t be known for months and that the counsel of prudence is simply to wait and see?

“Because economic forecasting is far from a precise science,” Mr. Bernanke judiously wound up yesterday’s testimony, “we have no choice but to regard all our forecasts as provisional and subject to revision as the facts demand.”

Would that the same standard were applied to monetary systems, which too could benefit from revision and reconsideration. It is asking a lot of our central bankers to succeed at the black art of price control. At some point some senators might just want to ask a testifying Fed chairman whether it may be time to stop trying.