The obituaries for liberal reform will have to wait a while, because John Gardner -- the placid, quiet voice of liberalism -- has detected a new mood and feels it will work.

"There's a feeling, one that I find most appealing, one that says we've got to shape up," says Gardner. "Everyone going his own way just isn't working. There's more unexpressed power out there. And people feel very strongly about the absolute basic of human fairness, not just as an impulse, but as an intention."

Yesterday, the 10th anniversary of Common Cause, the citizens' lobby that Gardner guided from just another lofty-sounding solicitation in the mailboxes of would-be reformers in the early 1970s to an established and effective part of the political landscape, suggested one reason to reflect on the nature of reform.

Still another reason is the enormous leap in allegiance the conservative movement has recorded in the last few years and the strident criticism it has directed toward efforts like Common Cause. Recently, the attacks have come from the independent political groups, ones that were formed after the Federal Election Campaign Act of 1974. This was a successful effort of Common Cause that limited direct contributions to politcal candidates. Now those groups, which largely espouse right-wing philosophies, are the object of a Common Cause lawsuit, which was overruled by a three-judge court. Common Cause plans to appeal to the U.S. Supreme Court.

Gardner, a former Cabinet member under Lyndon Johnson and now the head of his own think tank, is unruffled, as were the national members of the group who crowded into the Dupont Circle Hotel yesterday. "I always felt we ought to be flexible about listening to any criticism but never vary in any basic tenet. We cannot allow money to corrupt the political system," said Gardner.

"You take problems as the occasion for greater resolve. The conservatives have the microphone at the moment, In the long run the American people don't want bought politicians."

Nan Waterman, former chairwoman of Common Cause and an official in Rep. John Anderson's bid for the presidency, said, "we feel our reforms are working, but reforms need to be reexamined, as well as the causes."

At yesterday's meetings any thoughts of identity crisis were quickly erased as the speakers called for a renewal, and some excavation, of the initial goals of Common Cause. They were searching for what Common Cause president David Cohen calls the "tonic of invention." And their mild compassion was buoyed by an increased membership last year to 224,000 after an earlier decline of one-third. Participating in the early sessions were Harlan Cleveland, director of the Hubert H. Humphrey Institute of Public Affairs, University of Minnesota; M. Carl Holman, president of the National Urban Coalition; Alfred Kahn, the Carter administration's chief inflation adviser, and Susan Paris Lewis, the special projects director for the Aspen Institute for Humanistic Studies.

To survive the 1980s (the topic of the panel), Kahn suggested a nonromantic coalition. "It's not surprising that the liberal reaction is largely romantic, and this is my oversimplication, but . . . energetic intervention in front of public service commissions . . . additional government spending, every one of these proposals denies the scarcity problem," he said.

Social problems, said Holman, need the combined efforts of middle-class families, who are limiting their children, and black teen-agers, the bulk of the hard-core unemployed, the women who gain from their own upward mobility and those who are locked into fixed incomes. "What we need, borrowing a thought of John Gardner, is a spirit of the village green, of what we have in common," said Holman.

Starting with a review of modern philosophy and physics, Lewis said she still felt the Common Cause belief was correct. "The individual does make a difference, and we should have joy in that idea, not Calvinistic gloom," she said. Cleveland strongly criticized President Carter's recent speech on the economy and Kahn's remarks yesterday for omitting international affairs. "If we can erase that line [referring to the division of domestic and foreign affairs planning and discussions] and can maintain that upbeat, can do, American attitude, we can get to the 1990s," he said.

The need for reform wasn't debated at the party the lobby gave itself at the Texile Museum last night but the question of direction was. 'First we have to deal with the whole question of paralysis," said Fred Wertheimer, the senior vice president. "People's frustrations are always heightened when the economy is in bad shape. This uneasiness is the end of the 15-year period, the withdrawal after Vietnam and Watergate. . . . People feel you have to work at strenthening institutions." Many of Washington's strategists clustered in the humid garden: Common Cause chairman Archibald Cox, presidential counsel Lloyd Cutler, attorney Charles Halpern, White House special assistant Anne Wexler, U.S. Court of Appeals Judge Abner Mikva, Federal Communications Commission chair Charles Ferris, Rep. Robert Drinan (D-Mass.) and Sen. Alan Cranston (d-Calif.).

For the future Cox had several ideas, beginning with an examination of the primary system after the November elections and the decentralization of the politcal process down to the neighborhoods. "I have said we have always boosted about Yankee ingenuity in a mechanical way. But the real American ingenuity is doing it yourself, and that's what Common Cause is doing."