Perhaps this offers a lesson in bias. It seems that during such bad times even the most respectable newspapers somehow needed to write an upbeat story for the holidays. Confidence-building is part of our culture, and it helps to explain confidence swings.

During the Depression, George Gallup began to compute confidence indexes. But sharp improvements in confidence, as reported in 1938 by Gallup’s American Institute of Public Opinion, did not spell the Depression’s end. Eventually, consumer demand did come roaring back— after World War II, contrary to economists’ widespread fears that the Depression would resume after the war.

Professor Garon details an attitude that Americans, more than people in any other country, have usually had about spending: we tend to think it’s O.K. for people to go into debt to buy gadgets or take vacations. According to this view, such activity will stimulate everyone’s imaginations, and ensure a vibrant economy with plenty of fresh enterprises and innovations. Americans even tend to think that debt burdens may not be so bad — that people in debt work harder to pay it off, again keeping the economic engine humming. We are relatively forgiving of personal bankruptcies, too: they provide a fresh start to allow spending all over again.

IN much of the rest of the world, Professor Garon documents, this approach has traditionally seemed morally repugnant — though until the current crisis, many people worldwide were slowly coming around to the American view.

Governments around the globe have long promoted pro-saving — that is, anti-spending — campaigns. Professor Garon notes that many of these campaigns flourished during wars, when frugality was a necessity to conserve resources. In World War I and World War II, government campaigns left a lasting impression that overspending was immoral and unpatriotic, and for most countries the campaigns did not stop when the wars ended.

The United States had such savings-promotion campaigns during those wars, too, but it gradually ended them afterward. By 1966, the United States had suspended its postal savings system — which encouraged savings by allowing people to buy certificates of deposit at post offices for as little as a dollar. Many countries still have such systems, as part of efforts to make saving seem convenient and patriotic.

Low consumer confidence during the Depression could have been caused partly by fear of war, many commentators said at the time. But it is hard to measure the validity of such claims.