By MIKITA BROTTMAN

A man goes to his rabbi and says he wants to divorce his wife because she has such filthy habits.

"What are these habits?" asks the rabbi.

"Oh, I can't tell you," says the man. "It's too filthy to describe."

The rabbi refuses, without hearing more information, to grant the man the divorce.

"Well, if I must, I must," says the man. "Every time I go to relieve myself in the sink, it's always full of dirty dishes."

An innocent joke? According to Gershon Legman -- the world's leading authority on the dirty joke -- there's no such thing. This joke, he claims, was told to him in Scranton, Pa., his hometown, in 1936 by a respectable Jewish woman of middle age, and -- as with all dirty jokes, according to Legman -- has much to reveal about the personal neuroses and proclivities of its teller. "Other than the obvious level of self-unveiling here, of the woman's unhappiness with her brutal and egoistic husband," writes Legman, "there is perhaps a further level, even better concealed, in which the joke complains of women's woes concerning the household chores that make her too tired and unready to enjoy her sexual life, here alluded to in almost infantile terms."

Legman makes the fascinating and persuasive case that a person's sexual anxieties can be determined through a close analysis of his or her favorite dirty joke, which carries a powerful clue to the teller's own psychological bent, one that the person is struggling to unveil without revealing it. "Your favorite joke is your psychological signature," he writes. And everybody has a favorite. "It's precisely in these favorites of every joke-teller, in his or her special repertory, that we may discern the face hidden behind the mask."

Bruce Jackson, a professor of American culture at the State University of New York at Buffalo, described Legman as "the Diderot of the dirty joke." Legman, who died in 1999, at the age of 81, remained estranged from the established world of academic sexologists, folklorists, and the cultural establishment in general, devoting much of his life to two enormous scholarly studies of the dirty joke. Yet although his relationship with the world of academe was always contentious and antagonistic, he was an erudite scholar whose knowledge of European erotica was unsurpassed, and whose work has an enormous amount to teach us about the way we think and talk about sex. Since his death, the importance of his work is becoming increasingly clear. In his obituary in The New York Times, Legman was described by Jackson as "the person, more than any other, who made research into erotic folklore and erotic verbal behavior academically respectable."

The year 1968 saw the publication of the first volume of what was to become Legman's magnum opus, The Rationale of the Dirty Joke (Grove Press) -- a work he'd been preparing for more than 30 years. This remarkable volume's 811 pages contain well over 2,000 jokes. But it is certainly not intended as a compendium to be brought out at stag parties or kept handy by the toilet. In part, the book serves to explain how such jokes are rarely "new" and seldom "invented," but all relate back to variants that have evolved from other times and civilizations, many traceable to the Renaissance or earlier. It also serves to illustrate Legman's claim that the majority of dirty jokes deal with a situation of highly charged sexual tension in which the teller of the joke has been forced to live. In fact, the function of sexual humor in general, he explains, is to reconcile us to the painful, unacceptable, or tragic aspects of the human condition. Consequently, the telling of the dirty joke permits a "moral vacation" of uncontrolled hostility; the laughter aroused by such jokes is less often of amusement than of relief, "when the ordeal of listening is over."

Self-educated in the New York Public Library, Legman began collecting examples of erotic humor and folklore at a young age. After a few years of literary hackwork -- writing privately commissioned erotic stories -- he eventually found a more stable position as a medical researcher for Dr. Robert Latou Dickenson, head of the National Committee on Maternal Health. The position allowed Legman to pursue his obsessive fascination with human sexual behavior. He was a proponent of free love who lived through the repressive social climate of the 1940s and '50s, and his research gave him an intellectual grounding in Freudian psychoanalysis, viewed through a strong sense of sexual and social idealism.

A passionately felt personal manifesto -- like all of Legman's work -- the Rationale boils over with learned allusions, psychoanalytic evaluations, value judgments, and irrational attacks. In the space of a single page, he might dabble in philosophy, attack medicine, engage in literary critique, and offer a personal anecdote about his intimate relationships with women. His prose is always full of liberating verve, color, and exhaustively documented diatribes, relieved from time to time by wonderfully slanderous attacks on famous people and attention to scarcely relevant minutiae. At one point, for example, apropos of nothing, he launches into a rant against the regression to the anal stage that he claims is behind the interest in deodorants.

"The natural odors of the woman are to be washed away as 'dirt,' and are to be replaced by the anal and genital secretions of deer (musk), skunks (civet), beavers (castor), and diseased whales (ambergris) at $30 an ounce. The natural secretions of the woman are free. In the battle between 'the neurotic modern regression to the anal stage,' expressed with the reaction-formation minus sign of an excessive interest in 'cleanliness,' white bathroom, and even kitchen fixtures, mentholated toilet paper, special 'body-odor soaps,' and 'chlorophyll' ex votos that make the human being (and bathroom) smell like a freshly creosoted chicken-coop, a few desperate avowals of wholesome interest in the natural body (though seldom in its natural odors) can sometimes still be found."

The Rationale was slammed by reviewers, who were baffled and shocked. Brigid Brophy, in the magazine The Listener, was particularly repelled by Legman's prose style, accusing him of "purple-faced passages of belly-laughable rationale."

What the reviewers seem to have misunderstood, however, is the fact that the main goal of Legman's scholarship was the reintegration and assimilation of apparently disparate things, so the private and intimate can be seen as existing in the same world and on the same level as a broader civilizational commentary. The subject matter and style of his work made Legman a target of derision in the world of "serious" academic scholarship, but his writing quickly became widely sought after outside academe, developing something of a legendary underground reputation. His circle included such literary iconoclasts as Jack Kerouac, Marshall McLuhan, Allen Ginsberg, and, later, Norman Mailer. By refusing to separate his personality from his academic work, by filling his scholarship with deeply felt emotions and prejudices, Legman became widely known and respected in that demimonde of "outside scholars" on the fringes of academe -- booksellers, ghostwriters, and those collectors of the obscure and arcane among whom he had always been most comfortable. His work was also significantly ahead of its time, anticipating some of the more personally integrated scholarship of cultural studies that emerged in later decades, particularly the work of scholars like Jane Gallop, Laura Kipnis, and Eve Kosofsky Sedgwick.

And in many ways, Legman's model of academic scholarship strikes us as eccentric only because of its extreme honesty. By refusing to abide by the rules of academic rhetoric, by refusing to respect disciplinary boundaries, by refusing to separate his private interests from his scholarly life, he consciously estranged himself from the academic establishment. In fact, in 1953, after the U.S. Post Office stopped deliveries to him ("obscene items" were regularly being confiscated), Legman decided to leave the United States for good. He moved with his wife to a two-room stone house in the south of France, where they lived in poverty, surrounded by his enormous library and a brood of stray cats.

His bitterness with the academic world was thenceforth expressed in his work, where part of his goal was to demonstrate the arbitrariness of scholarly rules and boundaries, and to reveal the self-interest and self-absorption of the scholarly establishment -- essentially, holding a mirror up to the academic world and showing traditional scholars something that they weren't prepared to face.

If he were writing in any other area -- literature, say, or art criticism -- perhaps Legman would have been taken far more seriously, his unusual personal style excused (or even encouraged) as a creative means of expressing some fascinating and radical ideas.

Unfortunately for him, however, he felt compelled to explore the fields of sexuality, which scholars have traditionally been unable to separate from the "objective science" of medicine, and folklore, whose methods also rely on rigidly documentary investigation. By constantly offering evaluations of behavior and situations and consciously making value judgments, Legman revealed that the "distance" and "objectivity" that scholarly writers have established in those areas are merely artificial devices intended to offset the many anxieties they have when writing about sex.

Legman is one of the scholars whose work is commemorated in a recent volume of essays titled Sex and Humor: Selections from the Kinsey Institute (Indiana University Press). The book, which accompanied an exhibition at the Indiana School of Fine Arts Gallery, is a collaboration between the gallery and the Kinsey Institute for Research in Sex, Gender, and Reproduction. About 170 items represented a wide range of material, from rare pieces of fine art to ephemera. The exhibition featured works by such well-known artists as William Hogarth, Hans Bellmer, and Jean Dubuffet, alongside previously unseen material from the Kinsey Institute archives, including anonymously produced drawings, photographs, comic books, erotic figurines, and commercially produced novelty items.

The catalog accompanying the exhibition included a foreword by Betsy Stirratt, gallery director of the School of Fine Arts; 42 black-and-white plates; an introduction to the Kinsey collections by the exhibit's curator, Catherine Johnson; and several other chapters. Some of those provided academic, historical, and cultural context for the objects on display, like the essay by the Kinsey-affiliated folklorist Frank Hoffmann on the humor of the "eight-pagers" -- short, erotic comic strips especially popular in the '30s and '40s, also known as "Tijuana bibles." Other chapters are devoted to a broader understanding of the ways sex and humor are conjoined, including a chapter on feminism and humor by Lenore Tiefer, a clinical psychologist and sexologist in New York, and a personal essay by John Bancroft, director of the Kinsey Institute.

Bancroft is one of many academic scholars and sexologists who have actively championed Legman's reputation as the world's leading authority on erotic verbal behavior. Legman's association with the institute goes back to the early 1940s, when Alfred Kinsey, then working on the first volume of what was to become known as the Kinsey Report, employed him to work as his New York book buyer.

Legman was obstinate and contentious by nature, and the job didn't last for long. In fact, his refusal or inability to compromise was a regular pattern in his life, rendering him essentially unemployable. It seems astonishing that he managed to work so prolifically without university financing, research grants, academic recognition, photocopying facilities, or even an indoor toilet. That poverty, however self-induced, gradually became a source of great acrimony to him, and he continued to publish passages of scornful vitriol about university professors, especially those in folklore departments. However, despite his difficult relationship with academe, Legman remained proud for the rest of his life of his early association with what was to become the Kinsey Institute, and as late as 1976 was still referring to himself as Kinsey's official bibliographer.

In a characteristic moment of honesty, after a lifetime spent studying them, Legman came to the conclusion that dirty jokes are really rather pathetic, and that what they have to reveal about the human condition is dreadfully sad. He once confessed in an interview that he didn't like any jokes at all, and rarely ever told them. "After they get that first nervous laugh, they're depressing," he said. "I'm a poor raconteur, and I never laugh. Maybe a little titsatibitsa laugh, but yokchata botcha -- hah hah hah -- no."

Mikita Brottman is a professor of liberal arts at the Maryland Institute College of Art. Her essay "Gershon Legman: Lord of the Lewd" is in the catalog from Indiana University Press that accompanied the exhibition "Sex and Humor: Selections From the Kinsey Institute."