THE HIGHEST praise may not be imitation. Maybe it's a plea for help. To bail out a doomed article, I once wrote Irving Howe, asking him where popular fiction got off and serious art got on. He said if he could answer that question he'd write the article himself.

Here in Howe's 30-year selection of 41 short pieces from magazines and newspapers are the reasons why those who read, write or think about literature turn to Irving Howe. He is what we mean by "critic" instead of "reviewer." While some have given him Edmund Wilson's mantle since Wilson joined the angels, others thought he should have worn it (as critic, if not man of letters) while Wilson was around. Howe writes magnificently and has exquisite sensibilities. Wilson bullied the language and had an authoritarian streak.

Howe seems to posses everything that most writing academicians (the U.S. is blessed or cursed with critics, thanks to tax-funded teaching jobs) only have parts of. His curiosity, especially about U.S. social turmoil and cultural evolution, takes in history, movements, philosophies, careers and occasionally a flash in the pan.

His reviews discover ignored writers like Crawford Power, John Williams, and George Konrad. They qualify without debasing the currency of Robert Frost and J. D. Salinger. They celebrate the inexplicable, intuitive art of Bernard Malamud and Flannery O'Connor. They contemplate the marks left on American culture by Lionel Trilling and Edmund Wilson, and some of the marks fighting for intellectual clarity left on these heroes.

Howe's reviews seem always to turn to the social origins of art. The axis of his work is that peculiar New York Jewish-immigrant romanticism that has taken Howe from Trotskyism to socialism and modern literature as, perhaps the best hope, however compromised, that enlightenment shall prevail.

To see why American literature has been driven to probe and search New World experience for meaning, read Howe's essay "Literature and Liberalism." To know Howe himself read his "Lionel Trilling: Sincerity and Authenticity" and feel his rabbinical struggle as he wrestles with the vulgarities of modernism and seeks the humane in our revolution of self-discovery.

Marvin Mudrick lives and writes in Santa Barbara, chiefly for The Hudson Review, where most of these 23 essay-reviews appeared during the past seven years. If I didn't know H. L. Mencken had died, I'd swear he was hiding out in academic California under an assumed name. Mudrick is a literary curmudgeon, a randy icono-clast and a delight. He provokes strange high - culture responses: snarls, laughs, hostility. Plus enlightenment.

Mudrick's titles suggests his bent: "Su Cosa Mi Cosa; or Busy Busy Busy" (a gamey review of the diaries of an indefatigable lecher, Samuel Pepys), "The Offending Member" (a less gamey investigation of Graham Greene's Lord Rochester's Monkey ), "Aged Eagles and Dirty Old Men" (a review of three books about the the very active Bertrand Russell), and "Old Pros with News From Nowhere" (a fiction chronicle that works over the best and brightest of 1973, including Nabokov, Cheever, Berryman and a dozen others).

Mudrick's reviews are typified by healthy length, discursive movement, precision of language, idiom and slang, an argumentative sense of humor that fits his intelligence perfectly, and a selective lack of charity. No living author (and few of the dead) can escape Mudrick's demand for perfection.

His standards are Jane Austen ("a great novelist"), Tolstoy ("the tensest and most irascible of great novelists"), and Chaucer, who Mudrick says, "sawed life in half and out tumbled hundreds of unpremeditated lives, because he didn't have the cast-iron grid of a priori coherence that makes reading Goethe, Shakespeare, or Dante an exercise in searching for signs of life among the conventions, compulsions, self-justifications, proofs, wise saws, simple but powerful messages, and poetry."

Loving giants makes Mudrick hard to please when he meets ordinary mortals. He calls John Gardner a "psychocritic" who practices "portentousness" and "self - aggrandizing purpose." Besides that, Gardner strikes Mudrick as a "drip." Robert Coles is the "unavoidable contributor of five hundred easy pieces on psychiatry to the liberal magazines," and in Cole's interviews "how seamlessly the native American tells the Anglo shrink's portable Sony what it aches to hear." Philip Roth0 has lost not only his bearings but his marbles." Nathalie Sarraute writes fiction that is "tiny, diffuse, and banal" and Kurt Vonnegut's Breakfast of Champions is still another "kiddie-book."

The temptation to quote Mudrick is the temptation to sin. He is on occasion cruel, if always clever. He is a habitual punster, and may his tires be flattened for it. His use of the series must be arrested. But it's the thought that counts, and Mudrick's is as bracing as fresh air. Literary egos and reputations need deflation. Criticism needs less fence-sitting. If Mudrick is tough and demanding he also succeeds in making the books he praises seem to require our reading. The woods are full of critics. There's only one Mudrick. CAPTION: Drawing, no caption, Drawing by John Ryan