LIVES ON THE LINE: The Testimony of Contemporary Latin American Authors. Edited with an introduction by Doris Meyer. Berkeley, Calif.: University of California Press. 313 pp. $25.LAST WALTZ IN SANTIAGO: and Other Poems of Exile and Disappearance, by Ariel Dorfman. New York: Penguin. $17.95, hard cover. $8.95, paperback.

Throughout the intellectual history of Latin America, the role of the writer has been intrinsically related to his sense of being, as if writing and being coexist symbiotically. Since independence from Spain, some Latin American writers have dared to speak openly in their respective societies and many have paid the price of exile, disappearance, or murder.

They have literally put their lives on the line in taking on the role of witness to a history of oppression. The Mexican writer Carlos Fuentes affirms that "to be a witness of Latin America, in action or in language, is now, and will be more and more, a revolutionary fact. Our societies don't want witnesses. They don't want critics. And each writer, like each revolutionary, is in some way that: a man who sees, hears, imagines and says; a man that denies that we live in the best of all possible worlds."

That's taken from "Lives on the Line," which consists of Doris Meyer's wise selection of 30 essays, 20 by some of Latin America's foremost writers. The essays cover what is perhaps the most dramatic period in Latin American history: the 1960s to 1986. The book begins with the Cuban revolution and continues through the military regimes of the 1970s in much of the region.

In their testimonies, the writers represented tell how they began writing and how they became aware of their role as chroniclers of a specific place and time. We hear the voice of Julio Cortazar, one of Argentina's most distinguished writers, who realized - in every sense of the word - the meaning of his own quest for his Latin American identity even though he lived in Paris for almost his entire life. The Chilean Jose Donoso wrote about and came to understand his native country, reconstructing it in his mind and imagination from Spain.

The Cuban political exile Guillermo Cabrera Infante tells how his first short story precipitated his arrest in Castro's Cuba. On the other side, Alejo Carpentier, whose opposition to the regime of the Cuban dictator Gerardo Machado (1925-33) caused his self-exile in Paris, speaks of how his writings, and those of many other Latin Americans, emerged during the revolutionary '20s.

Many women are present in this collection. Argentine dame of letters Victoria Ocampo speaks poignantly about her turbulent initiation into the patriarchal world of literature in the Buenos Aires of the 1930s. Also included is Elena Poniatowska, one of Mexico's most distinguished writers, who has dedicated herself to speaking for the invisible women of Mexican society, such as the washerwoman of her best-known work, "Here's to you, Jesusa." Rosario Ferre, a Puerto Rican, exemplifies the newer generation of Latin American women writers who continue searching for a voice of their own, not so much by looking to mentors from abroad, such as Virginia Woolf, but by listening to the voices and stories of the women of their home countries.

"Lives on the Line" is a tribute to those writers who defy censorship and silence in order to create. These testimonies have a sense of urgency, but they also express the hope and beauty of a region besieged by centuries of oppression and violence.

Ariel Dorfman is one of Chile's better-known writers living abroad. Like so many others of his generation, he writes fiction and political essays that deal with contemporary Chile and the dictatorship of Gen. Augusto Pinochet. Dorfman's most recent novel, "The Last Song of Manuel Sendero," describes a generation of fetuses refusing to be born until the political climate of an imaginary country - undoubtedly Chile -changes.

"The Last Waltz in Santiago" represents Dorfman's attempt to explore through poetry the daily lives of people living under a dictatorship. Intense and colloquial, these verses speak of a world of endless disappearances and torture, as well as the lives of relatives left behind to search for those who have disappeared. It's a symphony of distinct voices: a mother telling her daughter that the missing father is neither dead nor alive; a father hoping his son still lives because someone heard his scream from the torture chambers.

It is difficult to write about the missing, about the howls of those condemned to death, and Dorfman, in this straightforward collection, does not succeed completely. His lyrical voice is not convincing. I am not saying it lacks authenticity, but that these poems seem to have been written to advance a cause or an urgent need to wake up readers concerning the reality and atrocities of a dictatorship.