Two authors view the world; Solvency -- The Price of Survival: An Essay on American Foreign Policy, by James Chace. New York: Random House. $9.95.; History and Memory: A Stateman's Perceptions of the Twentieth Century, by Charles W. Yost. New York: W. W. Norton. $14.95.

America's dazed Democrats are now asking not only how they can fight back but who they are. In their search for identity and a new consensus, leaders among them could do no better than to refresh themselves and gain perspective by reading two serious books: one a terse, sinewy essay on economics and foreign policy by James Chace, managing editor of the magazine Foreign Affairs; the other by the late Charles W. Yost, a thoughtful distillation of a diplomat's perceptions and recommendations at the end of a career spanning four decades and most of the globe.

Liberals are likely to find more here to cheer them than conservatives. But both authors strike me as pragmatists capable of surprising those who would consing them to ideological predictability. Yost, for one, despite his dislike and distrust of Richard Nixon, worked for Nixon as ambassador to the United Nations.

Both writers compel the reader to think through not just the issues of the moment but the issues which are likely to be with us 10 to 20 years from now. With Chace, it is a matter of what to do about waning American economic productivity and a consequent diminishing of American leverage in foreign affairs.

With Yost, the great issues of the day are five which no previous human society has ever had to confront: the proliferation of nuclear weapons, the population explosion, the struggle for diminishing raw materials, the revolution in communications, and "the drastic compression in time of the social strains and transformations" which flow from the several revolutions of modern times.

Both authors provide an alternative to the Reagan message, which calls for a return to traditional ways. There are limits to American growth, the two writers say, and no turning back. Both men offer hope and solutions, but insist that the latter will require sacrifice. Both see a need for more rather than less government direction. They warn that the world could grow dangerous indeed for the United States over the next decade or two, and not just because of the Soviet threat.

Here is Chace's warning:

"The question for America . . . is how to conform her rate of consumption to her diminished productivity before a collapse of confidence in the American economy results in a collapse of confidence not only in the international monetary system, but in the United States itself."

He calls on Americans to "produce more while at the same time accepting, at least temporarily, a reduced standard of living. During such a time, the public and private sectors would join together to rebuild America's industrial base and to upgrade her transportation system, to develop new sources of energy while consuming less, to increase basic research and development, to construct modern factories and provide them with the most efficient machinery that technology offers. . . .

"Such a program could lead to bigger exports, low inflation, a more stable dollar and, in the long term, a higher standard of living.

"To rebuild America in this way or to accept gradual bankruptcy -- these are the choices before us.

"But the political difficulties standing in the way of such rational choices are severe," says Chace. "It is hard to imagine their being made at all until a great crisis is upon us -- which it is -- and perceived as such -- which it is not."

Yost, for his part, recommends a series of reforms and declares that if many of them are not instituted within the next decade or so, he would doubt the capacity of the United States to maintain its position of world leadership.

"The government of a nation aspiring to leadership simply has to be able to act more rapidly and more consistently, and its economy to perform more steadily and reliably. . .," Yost says.

The veteran diplomat recommends, among other things, shorter electoral campaigns occurring at longer intervals, impartially administered federal funds for most election financing, strengthening of the traditional political parties, a consolidation of congressional committees and further limits on special interest lobbies, more self-discipline in the congressional oversight of foreign affairs, sharp congressional pruning of military budgets, even sharper cuts in the personnel of government departments and agencies, and the creation of national service corps for all able-bodied young men and women.

His proposed economic reforms include the application of price and wage controls to certain commodities and services, tax reforms, a nonbinding national economic plan, and the nationalization of certain essential public utilities which can no longer be operated profitably by private enterprise. Like Chace, he predicts major resistance to any such reforms, at least in the initial stages.

"Nevertheless, all of them should appear in party platforms," he says. "If we become accustomed to hearing about them over a period of years, we might come to think of them as reasonable, even eventually practical and necessary."