SATURN IS THE "planet of detours and delays" according to Walter Benjamin, one of the six literary figures under examination in Susan Sontag's latest collection of essays. Sontag has an affinity with Benjamin, not only with avidity of mind but with his metabolism. She understands the saturnine mentality: the slowness, the attentiveness, the patience, the melancholy need to work, the solitude, the complexity of thought. "He had an eye for the treasures of meaning in the ephermal, discredited and neglected . . e. with . . . a loyalty to the traditional canon of learned taste," writes Sontag, the author of such justly famous essays as "Notes on Camp" and "Against Interpretation." He also went "against the usual interpretation."

In praising thinkers who have set her a standard of excellence and stamina, Sontag's criticism is a kind of spiritual autobiography. These essays about Antonin Artaud, Roland Barthes, Hans-Jurgen Syberberg, Elias Canetti, Paul Goodman and Benjamin are appreciations of men who have somehow made successful dramas of their mind. It is Sontag's thought, the pressure of ideas trying to realize themselves, which is the drama of this dense, stimulating, and often galling book.

Written in a prose that is clotted, repetive and frequently imprecise, Sontag's long essay on Artaud seems to personify his own inability to externalize his fierce inner life, to possess the thoughts that finally drove him crazy. Artaud's goal was to lose his body, to get beyond the flesh. His "Theatre of Cruelty" was one of many radical attempts at self-transcendence. Sontag shrewdly links Artaud's quest to the 1960s' flirtation with drugs, Eastern mysticism, madness and non-verbal theater, which mirrored Artaud's own experiments in the '20s. Artaud, as Sontag points out, succeeded by failing. His writing, his lacerated words are to Sontag an "event" through which "one can be scorched, changed . . . But there is no way of applying him."

Certainly his own attempts at theater were a failure; but Sontag is misguided when she tries to discuss his influence. "He has had an impact so profound," she writes, "that the course of all recent serious theater in Western Europe and the Americas can be said to divide into two periods - - before Artaud and after Artaud." Really? Meyerhold, Jerry Brecht, Vakhtangov, and even Stanislavsky have been far greater practical influences on serious modern theater. She also has a lot of twaddle to say about Artaud as a formulator "of what was eventually to become standard serious taste." Among her examples she cites Sam Shepard, the Theater of the Ridiculous, Michael McLure's The Beard , and Heathcote William's AC/DC who have as much relation to Artaud as gallstones to jewelry.

In her appealing portrait of the polymath Elias Cannetti, what Sontag rightly admires is his attention to thought, a lifetime devoted to the acquisition of knowledge. "His work eloquently defends tension, exertion, moral and amoral seriousness." Canetti puts his passion for intellect more humorously: "I try to imagine someone saying to Shakespeare, 'Relax.' For Canetti (and Sontag), the act of thinking becomes a means of denying death. She is almost wistful at his intellectual autonomy: "Rarely has anyone been so at home in his mind, with so little ambivalence."

Her essay on Benjamin also explores and celebrates the search for "peerless learning." The essay starts badly: "In most of the portrait photographs he is looking down his right hand to his face." How? Sontag quotes a collegue describing Benjamin's oratory: "He harangued . . . in a style ready for print." That phrase is far too felicitous for Sontag whose writing never smiles. She is much more at home describing abstract ideas than the simple details of observed life. "The book for him," she writes of Benjamin's habit of straying from the taken route in his travels, "was another space in which to stroll." Sontag communicates her fascination with her temperment and with the triumphs of his mind. Although the essay is a subtle appreciation of a difficult thinker, she fails to mention that Benjamin's dissertation failed (this changed the course of his life) because of its incomprehensibility. She hardly discusses Benjamin's relationship to Brecht, a glaring omission since Benjamin was Brecht's finest critic. But his flattery of Brecht doesn't quite fit into her picture of Benjamin as intellectual giant. She snobbishly seems to feel that the greatest German poet and playwright of the 20th century was not Benjamin's intellectual equal. "The prince of the intellectual life could be a courtier," she sniffs.

Sontag's best piece, the one in which she is most direct, combative, and astute in her analysis of politics and aesthetics, is "Fascinating Fascism," a brilliant demolition of Leni Riefenstahl. Sontag sees the attempt to rehabilitate the former Nazi film-maker as a symptom of the psychopathic times. She skillfully shows how Riefenstahl's photographs of Nuba tribesmen reflect the same fascist aesthetic preoccupations that led her to make Triumph of the Will : "a preoccupation with situations of control, submissive behavior, extravagant effort, and the endurance of pain; they endorse two seemingly opposite states, egomania and servitude." In their exalting of surrender, mindlessness, and in their glamorizing of death, Sontag shows fascist aesthetics to have a direct link to the detached contemporary camp styles that "theatricalize sexuality." In the punk styles that sport Nazi regalia she sees "a response to an oppresive freedom of choice in sex (and in other matters), to an unbearable degree of individuality; the rehearsal of enslavement rather than its reenactment." Sado-masochism, "the big sexual secret of the last few years," is the erotic manifestation of the fascist aesthetic, another sign of society's more exhaustion. Nowhere in her book is Sontag's voice clearer or more cogent. "now there is a master scenario for everyone," she writes of the emotional detachment. "The color is black, the material is leather, the seduction is beauty, the fantasy is death." Only here, in these bold connections, is the power of Sontag's thought irresistible and liberating. But it is sufficient to confirm not only her excellence but her stature as one of America's foremost critics.