THE POLITICAL SCIENTIST believes in the efficacy of pragmatic solutions to human problems: Blame the system or its leaders if something goes wrong, or "events" themselves. Find better leaders or invent a better system. Gain control of "events."

The literary moralist believes human problems are the result of defects in human nature itself or in the structure of the universe that are mostly without cure: Blame the creature (or its creator). Try to reform him if possible. Try to find cause for hope.

I make this distinction because Jailbird will undoubtedly be described by some readers as Vonnegut's new Political novel, or his treaties on the failures of liberalism, or Harvard, or the American way. Or his explanation of why Watergate was visited upon us, or his prescription;or the future, or possibly even the platform for his own candidacy in 1980.

Some of these characterizations are not far from the truth. (I have a feeling that Vonnegut would make a first-rate chief executive, as a matter of fact; but it seems unlikely he could ever be persuaded to run for the office.)

The narrator and protagonist of Jailbird, Walter F. Starbuck, is a former staff member of the Nixon White House who has been imprisoned for his "preposter ous contributions" to the Watergate scandals. The historical backdrop developed for Starbuck's tale of woe covers most of the last century, from an Ohio labor riot and massacre in 1894, to the Sacco and Vanzetti case and execution in the '20s, to the House Un-American Activities Committee hearings, to the contemporary workings of the largest conglomerate in the Free World (RAMJAC). It features cameo appearances by Richard Nixon, the ghost of Albert Einstein, Roy M. Cohn, Clyde Carter (fictitious third cousin to the president of the United States), not to mention various extraterrestrials.

But the central story of how Starbuck, the son of immigrants, goes from Harvard to the White House to jail, and then from jail to a vice-presidency of the RAMJAC Corporation, and then back to jail, is a fable in the classic tradition of the great American-Dream-Gone-Awry; and Vonnegut proves himself, of course, far more a literary moralist than a political diagnostician. He is, in fact, the same Vonnegut we have seen before, the thinking man's pop writer, his magnanimous soul brooding, this time, over an obscene cartoon that bears too close a resemblance to the recent American past.

Vonnegut is terribly disappointed by the behavior of his fellow countrymen. His Hoosier sense of human decency and honesty is positively outraged at the mess the country is in. He is, on the one hand, an inveterate injustice-collector, appalled by the unnecessary insults life has sprung on innocent people; while, on the other, he sings a lament on the failures and the incredible posturings and ineptitude of the "damned human race."

Yet for all his cynicism and hand-wringing, Vonnegut still finds cause for hope in the human capacity for ordinary kindness. Several characters in the novel are promoted from low-paying jobs to positions as vice-presidents of the RAMJAC Corporation solely because they show kindness to a stranger. The RAMJAC Corporarion we gradually discover, is not an evil conspiracy of white-collar criminals out to control the world, but merely the grandiose embodiment of the falling political dream of a former radical activist, now a benevolent shopping-bag lady who haunts the toilets in the sub-cellars of Grand Central Station.

Perhaps the most surprising aspect of Vonnegut's visison of the world is that he manages to laugh, deplore and show sympathy (even forgiveness) all at the same time. Vonnegut has become the Walter Cronkite of our literature, and we read him for his avuncular authority and charm and soulfulness as much as for the news he brings and his occasional silliness. We tend to overlook his weaknesses and mistakes as we would those of a kindly relative who is singing slightly out-of-key.

Jailbird reads at times as if put together from a goofy collection of index cards. Pet bugaboos recur, but their arrangement sometimes belies some essential culminating development.Gratuitious ironies and a few awfully tired jokes are scattered about a little too wistfully in the brew. Perhaps most distracting of all is Vonnegut's habit of punctuating a truly dramatic or exciting moment in his narrative with a fatuous banality such as "Small world" or "Live and learn" -- an apparent legacy of the "So it goes" refrain from Slaughterhouse-Five.

But we do, as I say, forgive him. His imaginative leaps alone, as seen particularly in the irreal science-fiction stories Kilgore Trout tells Starbuck in prison, are worth the price of admission, and show Vonnegut at his impressive best. His far-reaching metaphysical and cultural concerns, though sometimes couched as shrugs or grimaces, are ultimately serious and worth our contemplation. We are all victims of Time and Fate. Education is no guarantee of humanity, he reminds us, any more than religious affiliation is any guarantee of moral uprightness. Hypocrisy, selfishness and greed are everywhere across the land and are our enemies. The proper conduct of life is still a subject we have not mastered.