Half a century ago, the first hopeful issue of a new men's magazine emerged into the debt-sick funk of the Great Depression. Despite the times, it was aimed at natty upscalers of the silk-tie and grouse-hunting persuasion; despite the odds, it became not only a financial success, but a journal of indisputable significance to American culture.

Its name was Esquire. And its unstintingly touted, ad-fat 50th anniversary issue arrives on the stands today--bulging with 55 of the monthly's most memorable pieces and revealing all the glories and embarrassments of what Esquire has been and has become.

Naturally, it's a thumping success--and a chubby bargain at $3 for 450 pages. But then only a patent imbecile could have made it otherwise, given several thousand articles to choose from and the triumphant example of a previous "greatest hits" compendium, the 40th-birthday issue. This time the material is arranged chronologically to depict "How We Lived: 1933-1983" as a service to Esquire's 34-year-old average reader. "A lot of our people," says editor Phillip Moffitt, "have a very uneven feel for history."

Their read may exceed their grasp, but they'll be seeing some classics.

There's John Steinbeck on how his family defied depression in the '30s: "I remember one great meat loaf carried in shoulder high like a medieval boar's head at a feast. It was garnished with strips of crisp bacon cut from an advertisement in the Saturday Evening Post." Sinclair Lewis forecasting black revolution in 1945 and defending Richard Wright's anger over "the quiet torture" of black life. Ralph Ellison on the birth of bebop; John Cheever on suburban migration; Garry Wills on Nixon's Checkers speech; Richard Rovere on Sen. Joseph McCarthy, "a Caruso among ranters"; John Clennon Holmes on the Beats.

Many masterful pieces have been pitifully truncated. Among the amputees: Peter Maas on the 1944 air war over Saipan, Norman Mailer's portrait of the 1960 Democratic convention and the "elusive" JFK ("one could be witnessing the fortitude of a superior sensitivity or the detachment of a man who was not quite real to himself") and Gore Vidal's acerbic 1967 essay "The Holy Family," about the Kennedy Cult--"the deliberate creation of the Kennedy family and its clients."

But many appear at length, including Joan Didion on the anthropology of shopping malls, William Greider on post-Watergate media blues and the blandness of Jerry Ford ("people think to themselves: I wouldn't buy a used car from him either, but maybe I could sell him mine") and Ron Rosenbaum's still astonishing expose' of "phone phreaks" who beat the Bell system.

And there are brain-spraining time warps. In 1962 we find Gloria Steinem proclaiming that coeds have discovered premarital sex and warbling excitedly over "the first completely safe and foolproof contraceptive pill." There's a reprise of '50s argot. (Remember churchkey for can opener, daddy-o? Or slip me some skin, rumbles, fruit boots, passion pits? You said it.) And Kurt Vonnegut on Maharishi Mahesh Yogi, the giggling guru: "What kind of holy man is it that talks economics like a traveling secretary of the National Association of Manufacturers?" Conspicuously absent: The curvaceous Varga Girl, created in World War II, who raised both morale and hormone levels in the foxholes.

Every spare inch is emblazoned with an editors' orgy of self-congratulation, from Moffitt's smug foreword to the back cover, which brays: "It is indeed extraordinary that any magazine should reach age 50 with its original vitality and character so unchanged by time."

Of course, this is preposterous. Esquire has changed with our tastes; and our tastes are debased, as this chronology amply demonstrates. Compare the purport--the simple human heft--of the subjects treated in the early decades with the relentless trivialization beginning 20 years ago. As historical context was leached from our lives and traditional forms of social superiority became confused in the demotic convulsions of the '60s, our definition of sophistication shifted: from a sense of cultural continuity to an obsession with the merely new and a lust to portray it with disdain.

No triviality--from Studio 54 to hot tubs to Valley Girls--was too vacuous to go uncontemned; and as words like "kitsch" and "camp" gained currency, the credo of the neo-sophisticate became: I condescend, therefore I am. See Gay Talese's piece on Vogue models or last year's gaping inanity about barroom social-climbing in New York, with such ornamental diction as "ditsy," "nerdy" and "yikes" (sounds like an accounting firm). And ask yourself if Cheever or Lewis or Steinbeck would have read them.

Also notice, on your way down the decades, how the voice shifts. As the first-person integrity of the New Journalism collides with the infantile self-absorption of the '70s, it produces a new narrative mode--the Narcissistic Confessional. Here the credo is: I feel it, therefore it must be important. And the more squalid the candor, the greater the self-aggrandizement.

Hence we find Sally Kempton actually writing in 1970: "I have noticed that when I feel most militantly feminist I am hardly at all interested in sex." Not, perhaps, the apex of intellectual endeavor--but she is hardly alone. The pronoun "I" appears five times in the first sentence of Dotson Rader's piece on the end of the antiwar movement. And Harry Stein begins a recent column by discussing a magazine article in which "there was the woman I live with explaining our abortion." Yikes. (An exception: Nora Ephron's "A Few Words About Breasts," in which the first person is both appropriate and hilarious.)

Yet, in a sense, Esquire has returned to its original character. Its creator was a Chicago menswear flack named Arnold Gingrich, who in an essay here describes "the Arrow Collar Man" as "the model we all grew up admiring." (Not Socrates or Jesus, mind you, but an anonymous cotton nape!) He aimed his creation at "that class just below knighthood--the cream of that great middle class" (hence the name), and dedicated it to "The Art of Living and the New Leisure." But Gingrich proved a superb editor, and Esquire came out of the sartorial closet, evolving into a forum for the best in American prose. After his death in 1976, the magazine floundered until Moffitt and partner Christopher Whittle bought it in 1979.

They promptly re-deified the Arrow Collar Man, embodied in the new slogan, "Man at His Best." In practical terms, this has meant a spate of dandified fashion issues and "drinking guides," a new travel spread to start this fall and an infatuation with "self-care" tips bursting with brand names. Such preening fatuity advances civilization not one inch. But Moffitt says his readers require it: "We've become so dramatically more internally oriented," and the new American male is "committed to learning about himself" and developing "sensitivity to emotions." (The advertisers know it. A DeBeers ad here reads: "I never thought of wearing a diamond. Until I met a woman who thought I should." Thorstein Veblen wept.) Hence the emphasis on "lifestyle" subjects and whiny unbosomings like last November's "Father Love."

America loves it. Circulation is up to 650,000. Ad revenues rose 75 percent last year, and Media Industry Newsletter rated Esquire the fastest-growing magazine of 1982. It has spun off Esquire Press to publish such cash-catchers as its recent "How a Man Ages." TV and movie projects are aborning. And the audience is building, although "our people," Moffitt says, "are those who care for the reading experience. It's not a majority. We're never going to be a 3 million circulation magazine."

Maybe not, if it follows the illustrious heritage of its first four decades, remaining courageous enough to run sizable and significant articles for a public whose attention span can be measured in microns. Maybe so, if it insists on pandering to boudoir vanity and epicene egocentrism--becoming a sort of tomboy Cosmo and hastening our decline into a nation of blow-dry nitwits.

Fifty is a good age at which to reflect on Nietzsche's warning: Stare long enough into the abyss, and pretty soon the abyss begins to stare into you.