An opera singer who had to keep silent for a week to preserve his voice later told me that during that time he saw pain in the faces around him, pain he'd never noticed before. The sculptor Marisol, now 77, has lived much of her life in relative silence, speaking only when necessary and then in monosyllables, answering most questions with a simple "yes" or "no" in a high, whispery voice. She expresses herself more naturally with her large, empathetic eyes and rare but surprisingly warm smile. Clearly she encounters the world as an observer and is acutely aware of the pain of which my friend spoke—that visible in the faces of others, as well as her own.

In Marisol's three-dimensional portraits, assemblages of found objects, plaster casts and blocks of wood that she has carved or drawn upon, the faces are the most realized aspect and the eyes the most conspicuous. Her subjects range from ragged children of the street to people of prominence, yet even when they are celebrity icons—such as Picasso, William Burroughs, Martha Graham or Desmond Tutu—she looks for the signs of vulnerability that reflect their humanity, their commonality with others.

In the art scene of the '60s and '70s, Marisol was herself an icon. As beautiful as a film star and as enigmatic as her pal Andy Warhol, she was one of the few women associated with the Pop art movement. Born Marisol Escobar, in France, of globetrotting Venezuelan parents, the artist, like her older friend Louise Nevelson, studied in Europe before working in the U.S. with legendary painter and teacher Hans Hofmann. In the '50s she began to experiment with Cubist-based assemblages, scavenging discarded wood from the streets of the then industrial neighborhoods of Tribeca and SoHo, and in 1958 she had her first solo exhibition at the Leo Castelli Gallery. Her work reveals influences as disparate as Pre-Columbian and Native American art, the Italian Renaissance, folk art, Dada and Surrealism, and it combines psychological insight, social criticism and satire to explore a range of emotions in contemporary life.

The works in the small recent survey at the Neuhoff Edelman gallery in New York were markedly uneven in quality. Respectful as her intent no doubt was, it's now difficult, for instance, to view Marisol's carved wooden figures of American Indians as much more than kitsch. And the ceramic life masks she made of herself, some scarily disfigured, when combined with hair pieces and macramé, can end up looking, at their worst, like '70s fetishist craft projects. However this show was never intended to be a "best of" retrospective, but rather a display of pieces from 1960-2007 that Marisol had saved for herself. Newly unearthed from her vast and supremely cluttered Tribeca studio, these include finalized works as well as arrangements of furniture and fragments of unfinished sculpture. Although reclusive in recent years, Marisol took an active role in the selection and presentation of the work in the show, which included enough truly excellent pieces that it was, in the end, an informative and even moving tribute to a significant artist.

An early sculpture, Couple 1 (1965), is surrealist and fabulously ironic, presaging the feminist issues that were to surface in the following decade—and it brings to mind the recent study, widely commented on in the media, concluding that women suffer physically when they refrain from expressing themselves in disagreements with their domestic partners. The male and female figures in this piece are rendered in life-size pencil drawings on two vertical blocks of wood faced with stainless steel. The man's clothing dominates—in the form of a flatly painted, bright red sweater—while hers is barely noted, except for black boots, a sign, perhaps, that she wants to flee. Their heads are both made of additional, squarish blocks of wood. The metaphor is humorous and hardly subtle—they are "blockheads," and he, clearly, is a "blow-hard" who has, in place of a face, a white nylon windsock held aloft by air currents from an electric fan. By contrast, the head of his female counterpart seems imprisoned in the block, from which she peers through a round portholelike opening. Her face, a lifelike rendering in pencil on a concave plate of polished mahogany, betrays vulnerability, and in her expressive dark eyes, extreme sadness. She's obviously trying to put up a good front even as she verges on tears; Mr. Windsock, concerned only with himself, is oblivious to her distress.

Although Marisol has made many portraits of famous people who inspire her, this exhibition included only one: Desmond Tutu, a likeness of the South African cleric and activist, made in 1988, four years after Tutu received the Nobel Peace Prize. Roughly hewn of wood, his head is balanced atop a 4-by-6-foot plywood panel painted purple to indicate his robes, with electric light shining through a cross-shaped cutout where his heart would be. His eyes are shielded by sunglasses, also carved, that are coated with shiny paint to suggest the sun's reflection. A disembodied hand clutches his bishop's staff. Marisol's combination of realism with abstract geometric forms—as with Tutu's rectangular "robe"—has the unexpected result of making her characters seem more alive rather than less. Instead of being frozen in time and space, they are part of a greater play of contrasting esthetic components, from which they draw considerable vitality.

Children, especially those who have been abandoned, neglected or subjected to other kinds of suffering, are a theme Marisol has returned to from time to time. Perhaps in response to the traumatic loss, at the age of 11, of her own mother, she particularly identified with John F. Kennedy, Jr., whose famous toddler's salute to his father's cortege Marisol chose to replicate in 1996—at a time when she frequently saw the grown man walking on the streets of their Tribeca neighborhood. By now one would think the oft-reproduced image would be too hackneyed to make a plausible subject for an artwork, but Marisol gives it new life. The carved wooden face of the boy has an obedient yet perplexed look that not only reveals his childish lack of understanding, but also uncannily foreshadows his own untimely death. From his tiny pedestal, he reviews the miniature funeral parade that Marisol has ironically configured with carvings of toy wooden soldiers.

Other children Marisol has portrayed were not always born into such privileged circumstances. Examples in this exhibition were the life-size Child with Empty Bowl (1987) and Cuban Children (1995), all roughly hewn from raw chunks of wood. The Cuban children are truly desperate—their faces are contorted, and one even has a spike driven into his head—but Child with Empty Bowl, like the Kennedy portrait, gains emotional power from its greater complexity. With his armless body made from a log, his legs crossed, and his knife and fork forming an X signifying the lack of food on his plate, the child's face nonetheless shows optimism—an indication that, like Kennedy, he's not yet conscious of his true deprivation

While most of the other Pop artists were responding directly to media representations of the American Dream, Marisol shows its human side, and in many ways, its cost. In Marisol's world, the downtrodden and the heroic are given equal weight, since her work is born of a desperate need to understand the nature of the human circumstance, common to us all. When she reached her 50s and faced the second half of her life with her renowned beauty in decline, she decided to go scuba-diving. When she returned to her studio, two years later, she embarked upon a stunning series of works portraying old people. The series includes her father, and also her artist hero Georgia O'Keeffe at 90, their wrinkles and gnarls emphasized by the grain of the wood in which she rendered them. It was as if, by studying them so closely, she was taking lessons in being old.

This is the way Marisol has spent her life-watching from her silent perch as human nature unfolds before her, then making sculpture that shows how people expose themselves when they think no one is looking. In the end, of course, the person she reveals most tellingly is herself.

"Marisol: Works 1960-2007" was on view at Neuhoff Edelman, New York [Sept. 20-Oct. 22, 2007]. It was accompanied by a 64-page catalogue that includes an essay by Carter Ratcliff.