THE attributes of Arab identity have proved quite a challenge for Americans in the last decade. Throughout the 20th century most United States citizens went along quite happily without expending a thought to, say, the difference between Sunni and Shiite Muslims. This was of a piece with a general climate of nonchalance about all things foreign. In a speech in Brasilia in 1982, Ronald Reagan infamously offered a toast to “the people of Bolivia,” a gaffe that probably did him more good than harm on his home turf. Since 9/11, the days of willful ignorance about the Arab world are gone forever, or at least there is a pretense they are. Now, just when it looked as if more or less everyone, politicians included, was close to getting the Sunni-Shiite thing down, along comes Amin Maalouf with his lovely, complex memoir, “Origins,” to remind us that Arab identity is as fluid, unsettled and ever-changing as the Mediterranean Sea where it kisses the shores of Lebanon, his country of origin, and France, where he has lived for the last 30 years. Maalouf is a writer of historical fiction (his novel “The Rock of Tanios” won the 1993 Prix Goncourt), a sometime opera librettist and a quirky historian — in “The Crusades Through Arab Eyes,” he brilliantly reconstituted a semi-documentary narrative from “the other side.” He is also a polemicist on behalf of the mongrel life. His 1998 book “Les Identités Meurtrières” (translated into English two years later as “In the Name of Identity: Violence and the Need to Belong”), about the vagaries of identity and the dangers in cleaving too hard to the national model, took on a trenchant identity of its own after 9/11. Here was the clear, calm, cogent and persuasive voice from the Arab world that it seemed everyone in the West had been waiting for. In that book, Maalouf argued, like Primo Levi in “The Periodic Table,” for the salience of marginalized groups, “frontier dwellers,” to the societies they inhabit. By paying attention to the mix and match of minority life, majorities smugly entrenched in fixed identities might be encouraged to get a grip on their own, almost certainly diverse, selves. The dangers of not doing so are clear. “Those who cannot accept their own diversity may be among the most virulent of those prepared to kill for the sake of identity, attacking those who embody that part of themselves which they would like to see forgotten,” he wrote. In “Origins,” Maalouf puts theory into practice by charting the wayward journey of his own family. The Maalouf family on the cusp and into the first decades of the 20th century is a challenging and charming blend of Catholics, Protestants, open thinkers and Freemasons, and sometimes a satisfyingly incongruent combination of two or more of these affiliations. There is even a Mormon branch in Utah. But the family's allegiance is first and foremost to the mountain villages of Lebanon, and from that unrolls a variety of commitments to place, family, religion, region, state, language, business, poetry and high thought. The Maaloufs are also somewhat taken with the idea of exile as an experience to broaden the mind rather than a loss of home to be endlessly lamented. In “Origins,” Maalouf focuses mainly on his grandfather Botros, a schoolteacher who, having failed in business (he wanted to grow tobacco in the Bekaa plain), lives instead “between notebooks and inkwells”; and on his more successfully entrepreneurial great uncle Gebrayel (his grandfather's younger brother), who left Lebanon in late 1895 for the United States and three years later for Cuba. They are a study in contrasts. Botros, a dandified intellectual determined to bring enlightenment to his corner of the mountains, scandalously refuses to have his children baptized, sets up a “Universal School” and roams his village bareheaded in a suit and cape, while Gebrayel establishes a successful retail business in Havana, only to die there under tragic circumstances. Amin Maalouf's forebears include a Melkite priest, Theodoros, and a tragic hunger artist, Botros's unnamed nephew, who starves himself to death because his father will not let him study literature. The memoir is also flecked with delicious family anecdotes: a young aunt unwinds her tresses on her way to bed when her excited father calls out from the kitchen where negotiations have been in progress, “Zalfa, do up your hair again; we've married you off!” Why look back? William Blake strongly advised driving your cart and your plough over the bones of the dead, and Maalouf is frequently tempted by the idea as he travels from his home in Paris to fill the gaps in his ancestors' stories. In Cuba, where he locates his great uncle Gebrayel's home and discovers newspaper reports of his death, Maalouf often gets that “I should have stayed home and watched sports on TV” feeling, but he persists in his research. The descriptions of his brief sojourn in Havana — frustrations and impasses followed by an unexpected denouement involving a long-lost cousin — are the most gripping and evocative chapters in the memoir. In Cuba, Maalouf feels home but not at home. He drinks local rum, invites the Caribbean breeze to caress his face and ruminates on what might have been if his grandfather Botros and not his great uncle Gebrayel had made his way to Havana. Yet in the end, Maalouf doesn't only want to illuminate family history or amplify stories barely whispered for a hundred years; instead, he strives to reveal the fecund variety of his own family, of Arab life and history, of history itself. In doing so, he offers a lesson in the value of impermanence and shifting sands. “Barely a hundred years ago, Lebanese Christians readily proclaimed themselves Syrian, Syrians looked to Makkah for a king, Jews in the Holy Land called themselves Palestinian ... and my grandfather Botros liked to think of himself as an Ottoman citizen,” he writes. “None of the present-day Middle Eastern states existed, and even the term ‘Middle East' hadn't been invented. The commonly used term was ‘Asian Turkey.' Since then, scores of people have died for allegedly eternal homelands, and many more will die tomorrow.” Identity is writ not in stone but on water. All the more absurd, then, when it is used — in a manner increasingly common, especially among our hopeful politicians — as a credential. Am I, for example, suitably qualified to represent the unemployed in contemporary Poland because my grandfather hailed from Piotrokow more than a century ago and never had a job in his life? In her old age, Amin Maalouf's grandmother Nazeera knitted him a white winter scarf so long that on chilly Paris nights he has to wrap it around his shoulders “several times so it won't drag on the floor.” Maalouf wants nothing more than to unwind the long scarf of memory and history, not to make a claim, but in celebration of human dignity, endeavor and “wanderers who have lost their way.” He is one of that small handful of writers, like David Grossman and Ayaan Hirsi Ali, who are indispensable to us in our current crisis. Jonathan Wilson is director of the Center for the Humanities at Tufts University. More Articles in Books __