This year's striking progress against inflation raises two questions of major import to Americans and their recession-mired economy:
* How safe will these gains prove to be, when the economy finally breaks its shackles and takes off again?
* Has the cost of wringing inflation out of the economy been too high in terms of lost jobs?
Consumer prices this year are likely to rise less than 5 percent, compared with 8.9 percent in 1981, 12.4 percent the year before, and 13.3 percent in 1979 .
November's 0.1 percent hike in the consumer price index - bringing 1982's 11 -month total to 4.5 percent - shows how rapidly the fearsome balloon of inflation has subsided.
Measured in two ways - consumer and producer, or wholesale, prices - inflation this year bids fair to be the lowest since 1976.
But the cost of these gains is painfully apparent. Nearly 14 million Americans are jobless, the highest percentage of the US work force to be unemployed since 1940, at the tail end of the Great Depression.
The jobless total includes almost 12 million people actively looking for work - 10.8 percent of the work force in November - plus nearly 2 million ''discouraged'' workers, no longer counted on the jobless rolls because they have given up the search for work.
This represents a classic case of the inflation-unemployment seesaw. When one comes down, the other goes up. Few economists profess to know how to break this tragic link.
A preliminary estimate by the government, meanwhile, shows the nation's gross national product (GNP), or total output of goods and services, shrinking at a 2. 2 percent annual rate in the October-December quarter.
Although this ''flash'' estimate will be revised later, the figure gives little assurance that the current recession - now the longest and deepest since World War II - has relaxed its grip.
Some experts say the jobless rate may top 11 percent before it begins a slow erosion back to the 9 or 10 percent level late in 1983.
Two reasons are given for this gloomy forecast. Economic recovery is expected to be slow, and many employers will try to get more work out of fewer people rather than rehiring laid-off workers quickly.
Already this tendency is showing up in greater productivity, or output per hour of work. While productivity growth is a plus for the economy, it bears out the assumption that the jobless rate will fall very slowly.
''Before the recession,'' says one businessman, ''I employed 1,300 people. Now I'm down to 500. When business picks up, I'll go back to about 700, not all the way up.''
Final figures for GNP performance so far this year show a 5.1 percent drop at an annual rate in the first quarter (following a 5.3 percent decline in the last three months of 1981); 2.1 percent growth in the second quarter; and 0.7 percent growth in the July-September period.
The recession and attendant high unemployment trace back in large part to the deliberate slowing of the economy by the Federal Reserve Board in an effort to squeeze out inflation.
So far as inflation is concerned, the Fed's tight money policy has worked. Whether the cost exceeds the gain will be answered subjectively by Americans who have lost jobs and by those many other millions - those with jobs and retired people - who applaud progress against inflation.
The question then becomes: Will these gains be permanent?
Experts measure inflation by computing the impact of many factors, which can be boiled down to ''volatiles'' - the price performance of such things as food, energy, and housing - and by ''unit labor costs'' (ULC).
No early upsurge of prices is expected from the volatiles. Housing and oil costs are likely to remain stable, possibly even decline.
What about the importance of ULC, made up of hourly compensation (wages) to workers plus productivity?
''By and large,'' says a new study from the American Enterprise Institute, ''as ULC goes, so goes inflation. . . . Over the whole period from the beginning of 1963 until the fall of 1982, the average annual rates of increase were 5.5 percent for prices and 5.6 percent for ULC.''
Labor costs, the study points out, account for about 70 percent of the total cost of producing an item or service. Clearly, experts agree, soaring wage and benefit gains achieved by trade unions in recent years pumped up the nation's underlying inflation rate.
For two reasons, that trend has slowed markedly. Workers in depressed industries have accepted low wage gains or none at all. Second, productivity has been rising.
''During the fall of 1982,'' says a senior Fed official, ''wages were climbing at a 4 to 5 percent annual rate. Productivity was growing just about as fast.''
So long as wages remain in line with productivity, inflation does not occur. All this makes the inflation outlook over the near term relatively bright, though the real test will come when recovery sparks new wage demands among workers.