ALTHOUGH MANY PEOPLE considered Roland Barthes a likely heir to Jean-Paul Sartre's central position in French intellectual life -- at least until Barthes' untimely death, which came, in the spring of 1980, less than a month before Sartrehs -- the two thinkers were actually quite dissimilar. Unlike Sartre, the system-builder, Barthes was a miniaturist, a lapidary, more interested in the small but radiant insight than the comprehensive structure. In his seminars at the College de France, he often counseled his students to pay close attention, when writing, to cross-outs, slips-of-pen, stray marginal comments, for in these little inadvertent asides they might find real illumination. Barthes himself was just such an exploiter of the fertile aside; indeed, his work stands as an example of what a nimble mind might do in the small alleyways of thought, particularly when the broad avenues have been too busily trod. A discoverer of novel possibilities within the larger, more familiar structures, he was very much a thinker of our time.

As a young man, Barthes explored the dramas of ancient Greece and 17th-century France: those most classical presentations of man's encounter with tragic limitations and the larger mysteries. In the course of his career, he moved back and forth among literary and cultural criticism, sociology, structuralism, semiotics, taking from each discipline what was useful (what was for him of intimate value) and leaving upon each the traces of his own distinctive thought. The drama of his intellectual life consisted precisely of his struggle to balance the reductivist tendencies of these disciplines against a more personal, whimsical, even poetic vision of human truth; a struggle, one might say, between objectivity and subjectivity, mind and heart, thought and feeling.

This was significant drama, and Camera Lucida provides its last act. Setting forth as an inquiry into the "genius" of photography, it brings to conclusion (in ways almost uncanny) those intitial investigations into the power of classical theater. For one of the points made in this little book is that photography touches art "not by Painting . . . but by Theater," that it aquires its power through a dramatic presentation of its subjects.

Barthes begins his study with an ambitious statement of purpose: "I wanted to learn at all costs what Photography was 'in itself,' by what essential feature it was to be distinguished from the community of images." That phrase, "at all costs," is not rhetorical. One cost -- significant for Barthes -- is the virtual abandonment of semiotics, structuralism, and other methodologies ("discourses") in which he had grounded much of his earlier work. Leaving behind the generalizing sciences for a science of the particular, he starts with the few photographs that had strongly affected him and, making himself "the mediator for all Photography," attempts to formulate a definition of this art.

The climatic moment of his quest comes when he discusses his attempt to find, among a collection of old photographs, something that would suggest the uniqueness of his own mother. The miracle of this search is that he succeeds. Looking at a picture taken of her as a young girl, he sees what he had so often sought words for: "a figure of a sovereign innocence." This photograph somehow transforms a typical girlish pose "into that untenable paradox which she had nonetheless maintained all her life: the assertion of a gentleness." For Barthes, this discovery is cathartic, a release from private despair; it also leads him to the essence of photography -- its power to reconcile the spectator to the related mysteries of time and death.

But from what in the photograph does this power arise? Barthes explains that it arises from the troubling relationship between the subject and the photographed image of the subject -- a relationship that is not representational but presentational (even allowing, as he does, for the flattening effect of the photograph). Against those who credit the painter and his systems of perspective and framing with the rise of photography, Barthes credits the chemist. By discovering the sensitivity of silver halogens to light, the chemist made it possible "to recover and print directly the luminous rays emitted by a variously lighted object." The image, strictly speaking, is an "emanation" of the subject. Recovering the subject from out there, the flow of time, the photograph preserves the thing or being "that has been." This much is obvious -- platitudinous, Barthes says, emphasizing the root sense (that is, flatness) of the adjective. But, and here the fatal twist, what the powerful photograph emphasizes is the mortality of the subject, its inevitable passing. And what can we, the spectators, say about this spectacle? Almost nothing. Working somewhat in the manner of the ancient theatrical mask, the photograph caricatures "not the figure . . . but its very existence." It caricatures this existence by revealing its most important (though most readily forgotten) feature: the imminence of its non-existence. Neither a metaphor nor a fiction, the photograph mutely certifies that the "corpse is alive, as corpse."

Of what use this "dead theater of Death" -- this presentation of an essence that Heidegger, philosophically, and Rilke, poetically, both sought to express? Barthes urges that it is of greatest use: "For Death must be somewere in a society; if it is no longer (or less infensely) in religion, it must be elsewhere; perhaps in this image which produces Death while trying to preserve life." Without this spectacle to remind us of the terms of our life, life becomes trivial, even pointless.

But society, like individual man, seems able to stand only so much reality, and already it has done much to tame photography -- either by making it into an art (and thus robbing it of its "madness" by endowing it with so many sociological or esthetic functions -- "alibis") or by making it banal. The second threat is more serious. A world flooded by so many images comes to be dictated by images; the endless production of photographs ends by de-realizing "the human world of conflicts and desires, under cover of illustrating it."

No doubt, many will object to the extremity of Barthes' conclusions, his dismissal, for example, of technial and esthetic qualities as ultimately tangential to the genius of photography. His inquiry certainly runs counter to the interpretive approaches of art history and criticism, for Barthes insists that the photograph resists reading, that it is precisely in its "arrest of interpretation that the Photograph's certainty resides." And the least one might say is that his conclusions hold more for a certain group of photographs than for all photographs, a point to which Barthes himself would probably have acceded. After all, as he concludes, we have the choice either to subject the spectacle of the photograph to the "civilized code of perfect illusions, or to confront in it the wakening of intractable reality."

Whatever choice we make, we must credit Barthes for making clear the option