The ultimate question is, how long will this new-found thrift last? Many pundits, no doubt feeling dire and sober, have estimated that it may take as much as five years before large numbers of people return to spending money they don't have on luxuries that they don't need. However, for those of us who knew survivors of the Great Depression, it seems likely that America's flirtation with homegrown fiscal conservatism will last a lot longer.

In his last "Investment Outlook" letter, PIMCO's Bill Gross approaches this process as a matter of appetite. For many people, both the gluttonous and the frail, appetite is uncontrollable: while some can't seem to stop consuming, others can't force themselves to start. Both paths are dangerous, and Gross suggests that, unless we can find a way to control our appetites, the economy may well be hopeless.

With any luck, the unsustainable, out-of-control growth that characterized the past decade will not return for a long time. However, the opposite -- a desperate, penny-pinching fear of expenditure -- would be every bit as destructive. While the past few years have demonstrated the danger of consuming too much, one need only look at Japan's "Lost Decade" to see the dangers of consuming too little.

As academic models and market forecasting plunge to new depths of uselessness, how, exactly, can one plan his or her economic future in an economy with massive unemployment, even more massive worker underutilization and an ever-shrinking place for investors to park their money. The answer, Gross seems to suggest, is to adapt to a "new normal" growth rate of two percent.

Another route might be to consider what the survivors of the Great Depression did. After all, much of America's postwar boom was fueled by people who had firm memories of childhood deprivation. As Megan McArdle recently noted in The Atlantic, even in the middle of the Depression, sales of radios, refrigerators, and washing machines soared. Similarly, even in our current reduced economic circumstances, Netflix, General Foods and Wal-Mart are doing extraordinarily well.

The key point linking these two eras are that they both reflect a trend toward consumer adaptation. In the 1930's, items like refrigerators and washing machines (as well as toasters, electric chafing dishes, waffle irons, and electric percolators) made it easier for Depression-era hostesses to make do without servants. Similarly, Wal-Mart's cheap pots and General Foods' cheap meals make it easier for today's consumers to do without restaurants. In the same vein, just as radio enabled families to save money on the theater and newspapers, Netflix helps its users save money on movies and rentals.

The Great Depression didn't halt commerce; rather, it pushed it in a more functional, sustainable direction. In all likelihood, the Great Recession will do the same. After all, it's worth remembering that the postwar boom wasn't fueled on McMansions and Cadillacs; rather, it was the product of Levittowns and Chevrolets.