Maxima Moralia.

Removing, both shoes and socks and pushing, open an immaculately white door, you step into a dark enclosure. Once inside, the room's dimensions remain indistinct, and the material that makes for the deep, almost spongy quality of the floor unidentifiable. Though it recalls sand - and the experience of trudging along a beach on a moonless night - it is finer, silkier. The granules of this nameless substance have wafted into the air, making the atmosphere dense and close. That it is a bit difficult to walk - and to breathe - leaves you feeling vulnerable and slightly anxious. After your eyes grow accustomed to the darkness, a faint flicker of light is discernable at the far end of the room, where the air is suffused with a distinctive odor, subtle enough not to have been perceived until that moment. It is the smell of natural gas. This first room is connected to another, at whose end a lit candle, partially buried in the ground, emits a soft light. The candle's flame is tenuous, and the atmosphere magnetic, with dust motes forming something akin to an aureole around the flame. The sudden realization that you are standing in front of a lit candle in a room saturated with natural gas produces an acute sense of danger. Everything is set for an explosion, yet this explosion never occurs - the smell of gas, it turns out, is simply the product of a colorless chemical compound, and the soft floor a thick layer of talcum powder.

Volatil (Volatile, 1980-), an installation finally realized by Cildo Meireles in 1994 and recently reconstructed for his first full-scale retrospective, is complex in its poetics. If its sensory dislocations recall the perceptual experiments of the California Light and Space artists, the work's material properties set in motion a range of sociocultural assocations that point in another direction altogether. Somber and ceremonial in quality, Volatil evokes the candomble rituals performed on Rio's beaches (during which lit candles are placed in the sand and offerings made to the gods of Brazil's popular Afro-Brazilian syncretic religion) not so much to celebrate the ecstatic atmospherics of these ceremonies as to speak, metaphorically, of a more general kind of sacrifice. The sense of vulnerability and the persistent fear of suffocation one experiences in this installation conjure the country's oppressive political climate during Brazil's military dictatorship in the '60s and '70s, suggesting that Volatil can be read as a profane altar to the victims of those turbulent decades.

Though Meireles' work can clearly be placed within the tradition of Conceptual art, the degree to which this and other installations rely on the specific properties of their materials contradicts all the conventions of a movement more often associated with stark facture, with the very dematerialization of the art object. In Volatil, for example, the spectator, ill at ease and somewhat threatened, is constituted as a fragile, provisory subject - one unbalanced as much by an array of interlocked sociocultural references as by the assault on his senses. This preoccupation with the phenomenal realm, a constant in Meireles' work, has more than a little to do with the milieu from which he emerged.

Meireles belongs to a generation of Brazilian artists that includes, among others, Tunga, Waltercio Caldas, and Jose Resende, and that was heavily influenced by the Brazilian Neo-Concretists. The Neo-Concrete manifesto (collectively signed by, among others, Lygia Clark, Lygia Pape, and Amilcar de Castro, but presumably written by the poet and critic Ferreira Gullar) embraced Merleau-Ponty's view of perception as a function of the desiring body - and effectively broke with the then-dominant Concrete tradition (a variation of Constructivism closely related to the experiments of Max Bill and his Superior School of Form). Emphasizing audience participation, the Neo-Concretists developed a fluid artistic practice that collapsed traditional divisions between public and private, the corporeal and the intellectual, even religious ecstasy and critical action, a blurring of boundaries perhaps best exemplified by the works of Lygia Clark and Hello Oiticica.

Clark's lifelong investigation and extension of that central Modernist paradigm - the relation between figure and ground - began with a series of small abstract paintings, which were followed by hinged, abstract metal sculptures called "Bichos" (Animals, 1960-64) that could be endlessly refashioned, and culminated in numerous objects designed for therapeutic purposes. In a videotape of one of Clark's sessions, the patient featured is none other than Meireles' friend and contemporary, art critic Sergio Duarte. The radicality of Clark's project lay in her attempt to transgress the boundaries of traditional art practice, even of art institutions, in order to give visual form to the process of subject formation, much as Meireles' work was later to do.

A good deal of the power of the Neo-Concretist project and the key to its hold on the imagination of the succeeding generation lay in its effort to position itself in relation to international vanguardism while adopting a clearly oppositional role to the country's political situation. Oiticica, for example, combined the Modernist aesthetics of Concretism and popular forms of artistic expression in a series of works known collectively as "Parangoles," on which he embarked in 1964 - brightly colored, multilayered capes, tents, or banners that were carried by dancers and on which he would inscribe political messages. One can easily imagine the shock experienced by fashionable Brazilian society at the sight of the black Parangole samba dancers - from the favela of Mangueira - as they filed into Rio's Museum of Modern Art, during the opening of Opiniao '65 (Opinion, 1965), a group show that also included the work of Antonio Dias, Vergara, and Rubens Gerchman, among others.

Like the Neo-Concretists, the artists of Meireles' generation were engaged in a thoughtful reexamination of the foundations of Brazilian culture. Drawing on European critical and philosophical discussions, they founded magazines such as Malasartes and Parte de Fogo in the '70s and early '80s, publishing articles on contemporary art and literature as well as translations of French theory. They were equally attuned to European and North American art movements, in relation to which they assumed a critical stance. If Oiticica's Parangoles were a reaction against Abstract Expressionism and what he described as the complacency of Pop, Meireles took to task what he viewed as the passive, depoliticized nature of North American Conceptual art. His ongoing project Insercoes em circuitos ideologicos (Insertions in ideological circuits) - first conceived in 1970 and exhibited that same year in "Information," Kynaston MacShine's groundbreaking survey of Conceptual art held at New York's Museum of Modern Art - consisted of paper currency and Coca-Cola bottles inscribed with or containing subversive messages, which were then placed back in circulation. In '70s South America, Coca-Cola bottles were among the most obvious symbols of North American imperialism, and by filling them with messages of a highly political nature Meireles reinforced this association. One such message, "Who killed Herzog?," inscribed on banknotes in 1975, referred to a notorious case in which a journalist, accused of being a member of the Communist party, was brought in for "questioning" and then reportedly "hung himself" in his cell that very afternoon. Other messages were more philosophical in nature, posing such conundrums as "What is the place of the work of art?," a phrase clearly unthinkable without Duchamp's readymades or Conceptualism's critique of the "white cube." In a text published at the end of the '60s, art historian Ronaldo Brito proposed that Meireles' work be read as a set of tropes, conceptual axes that may not intersect, but from which it is possible to articulate some of the moments the work encompasses. One such trope is what Brito calls "the strategy of insertion," one opposed to the notion of originality and thus to that of authorship. Insercoes em circuitos ideologicos is less a work of art in the traditional sense than a proposed strategy: the fusion of art object and commodity that calls into question the systems in which they circulate; it is complete only at the moment when the strategy, one made possible by the work's medium, is appropriated by the audience and the audience becomes the author. Meireles' tactics clearly operate in both a literal and a metaphorical field: the insertion is both real (message in a bottle) and figurative (a short circuit in the commodity system).

If works like this make clear the strongly reflexive and conceptual nature of Meireles' oeuvre they do not tell us much about the perceptual or aesthetic subtleties that lend his installations their visceral immediacy and power. Take one of Meireles' most recent pieces, Fontes (Sources, 1991-92) - shown at the last Documenta - an allusion to the colors in Van Gogh's Wheat Field under Threatening Skies with Crows, 1890. The work consists of a room from whose ceiling hangs a vast number of yellow carpenter's rulers based on four different models. Covering the floor, also yellow, are 500,000 black numbers made of plastic, scattered as if by a blow. One thousand round clocks decorate the walls, the hands on each yellow face indicating a different time, the numbers placed at random in each quadrant. This dense shower of numbers, though beautiful, is disorienting since there are no stable referents to time or space. Measure appears in its purest, most naked form: as a will to instrumentalization, an elemental kind of violence cloaked in the mantle of the utmost rationality. In confronting us with systematic chaos, with the complete impossibility of obtaining knowledge from numbers, Fontes unties the Gordian knot that links experience to a horizon of utility: given that measure and value are the elements that organize economic systems, capitalism in particular, this piece mounts a critique of rationality by radically altering the signs that organize our perception of time and space.

In countries that suffered for decades under repressive right-wing regimes, it is impossible to think of aesthetic concerns as divorced from political and existential ones, hence the development of a complex formal language that conveys sociopolitical critiques. Such is the case with Meireles' O Sermao da Montanha: Fiat Lux (Sermon on the mount: fiat lux, 1978-79). Somewhere between an installation and a performance, this piece occupied nearly an entire room - black sandpaper covered the floor; large mirrors, inscribed with a sentence from the Sermon on the Mount (Mt 5: 3-10), hung on each wall. When Meireles first installed the piece, he recorded the sound made by the rubbing of the audience's feet on the sandpaper and then played back the recording via loudspeakers positioned throughout the room. In the middle of the space sat a stack of 126,000 matchboxes, surrounded by five bodyguards with the tough look of undercover policemen. The exhibition of the piece was canceled in '73, '75, and '78 - the first two times presumably for political reasons and the last because of a fire. It was finally shown in '79, though that exhibition lasted only twenty-four hours. In Fiat Lux the combination of dislocating sensory effects and political concerns is particularly strong: not only can it be read as a reflection on life under Brazil's military dictatorship, but the piece itself is extremely dangerous, literally on the verge of an explosion - all those matches resting on sandpaper. Fiat Lux violently realizes the fictional danger of Volatil, and stages the political critique mounted by Insercoes.

Forged by a constant return to and development of previous concerns, the links between Volatil, Fiat Lux, Insercoes, and Fontes point toward the curious logic that organizes Meireles' work. While his retrospective, now on view at the Boston ICA (organized by IVAM curators Nuria Enguita and Vicente Todoli) suggests that political concerns have receded in favor of an exploration of the perceptual aspects of experience, a very recent graphic project contradicts such a reading. For this piece, an assisted readymade, Meireles reprinted a section of an illustrated article from one of Rio de Janeiro's tabloids that showed several dead bodies, balanced on the kind of concrete tubes used in highway construction, reportedly left lying in the streets of one of the favelas or slums lining Rio's mountains. The headlines in the paper read "Exposicao Macabra: Parecendo obra de um artista louco, cinco corpos equilibrados grotescamente em manilhas na Favela do . . ." . ." (Macabre exhibition: resembling the work of a mad artist, five grotesquely balanced bodies were found in the favela . . .). At the end of three pages of sheer horror, Meireles wrote "Estetica como Etica, Etica como Estetica" (Aesthetics as ethics, ethics as aesthetics). Though it was a journalist who first photographed this dreadful arrangement of bodies, it is Meireles who enables the horror of the scene to erupt in all its disturbing violence - a violence linked not only to the dead bodies but to their obscene aesthetic appropriation by the press. The full meaning of the piece emerges when read both in the context of artistic practice - appropriation and contemporary variations on Duchamp's readymades - and of the political realities in today's Brazil, a country where widespread poverty and social injustice are consequences of an unequal distribution of resources, a condition that results, in part, from a market structure that obeys the rules of the so-called global economy. Meireles' work, located somewhere between aesthetics and ethics, reminds us how tightly they are linked.