ARTHUR C. CLARKE, a renowned scientist-cum-science-fiction author. Harlan Ellison, a self-avowed "scientific illiterate" who for over a decade has sought to dissociate his idiosyncratic work from the sf label. And Jean Marie Mathias Philippe Auguste Villiers de l'Isle- Adam, an impoverished 19th-century French aristocrat who, while actively loathing the scientific positivism of his day, made Thomas Alva Edison the hero of his only novel.

Although an unlikely trio of titles, Clarke's 2010: Odyssey Two (Del Rey/Ballantine, $14.95), Ellison's Stalking the Nightmare (Phantasia Press, 13101 Lincoln, Huntington Woods, Mich. 48070, $16), and Villiers' Tomorrow's Eve (University of Illinois Press, $17.95) nevertheless illustrate an interesting fact about the human mind. Namely, that even within the same personality the tendency to deny the supernatural in favor of a pragmatic empiricism may be at war with a tendency to do the very reverse. Empiricists pray on the sly; supernaturalists sometimes secretly rue their credulity.

Of the four major sf writers of his generation -- the other three are Robert Heinlein, Isaac Asimov, and Ray Bradbury -- Arthur C. Clarke probably has the best-deserved reputation for creating scientifically convincing narratives. In matters astronomical and technological he has few peers. His speculations about the moons of Jupiter, say, or the evolution of machine intelligence almost always have the inimitable ring of authenticity.

On the other hand, Clarke shares with Bradbury, the least well-grounded in the sciences of the four, a visionary intelligence that sometimes borders on the mystical. His early novel Childhood's End (1953), for instance, concludes with a scene of human transcendence that inevitably recalls the apocalyptic thrust of The Book of Revelations. Similarly, in 2001: A Space Odyssey (1968), astronaut David Bowman undergoes a portentous physical and psychological change that apparently adumbrates the transfiguration of the entire human species.

Now, almost 15 years later, Clarke has delivered 2010: Odyssey Two, the sequel to 2001, and it, too, bids fair to become a cinematic collaboration with Stanley Kubrick. Moviegoers everywhere, especially those fascinated by the metaphysical import of the original film, will expect to have some questions answered. First, what alien power brought about the mysterious metamorphosis of David Bowman? Second, for what reasons? And, third, in what awe-inspiring, transcendental way is this change going to affect the whole of humanity? In 2010 Clarke provides an acceptable answer for the first question, a gimpy one for the second, and a disappointing shrug of the shoulders for the third. Indeed, almost as a means of avoiding this last crucial issue, the sequel raises some fascinating questions of its own.

Why have American scientists joined with a team of Russian cosmonauts to salvage the abandoned spaceship Discovery? How have the unforthcoming Chinese managed to put a vessel en route to Jupiter without tipping their hand before its launch? What evolving life form occupies the Jovian moon Europa? What destiny beyond mechanical resurrection awaits the lobotomized computer Hal? How does the crew of the Leonov contrive to boost away from Jupiter before the opening of their "launch window"? Why must they do so? And are the alien monoliths fissioning like rectilinear amoebas above the planet's surface really "the cosmic equivalent of the good old Swiss Army knife"?

Let me confess: it is easy to be cynical about a best- selling work that so obviously has its roots in Clarke's previous association with Kubrick. Although I think the movie, once made, is likely to be worth seeing, the novel has a grayness, a palpable lack of pizzazz, at odds with both the physics and the metaphysics of its subject matter. Ponderous expository dialogue alternates with straightforward expository passages in which either Heywood Floyd, the book's primary focal character, or the author himself lectures the reader. Each chapter is custom-made for transfer to the screen -- although, as in 2001, Kubrick will almost certainly turn Clarke's more prosaic lectures into enigmatic visual symbols. Readers desiring the provocative pyrotechnics absent in the book can go the movie. Moviegoers desiring explanations absent in the film can purchase the book. (This, I believe, is the media equivalent of a positive feedback loop.)

A second confession: Clarke has striven heroically to outfit his characters with recognizable longings, prejudices, and fears. He has made a wholly admirable concession to feminist critics of his work by giving the Leonov a female captain and two female medical officers. Unfortunately, these women have little more psychological depth than does either Heywood Floyd or the disembodied intelligence of David Bowman, who comes back to Earth for reasons that seem jury-rigged for their special-effects value to the film. (Remember Topper? Remember The Invisible Man?) Furthermore, despite his physical transformation into "an embryo god, not yet ready to be born," Bowman evinces very little growth in those subjective dimensions that would make his metamorphosis meaningful as an evolutionary step. And, as already noted, Clarke avoids or postpones for yet another sequel -- 20,010: Odyssey Three?--the question of what Bowman's change presages for humanity at large. Instead, Jupiter becomes a second sun, a new life form approaches self-awareness on Europa, and Bowman continues to await the climactic Day of Reckoning that most readers will have expected to encounter in this novel.

Read the movie. See the book. Although I am glad that Clarke did not retire from fiction writing, as he threatened to do, after The Fountains of Paradise (1979), I am sorry that he has returned to print with a 288-page screenplay masquerading as a novel. If this is his final word on the religio-scientific theme of human transcendence, then he could have abandoned the game in 1968. If it is not, then 2010: Odyssey Two is a workmanlike stopgap effort, containing a half dozen or more flashes of Clarke's patented speculative brilliance, the writing of which has perhaps deferred that of a far more important novel.

By the same token, Harlan Ellison's Stalking the Nightmare is a kind of stopgap collection from a speciality publisher. (Strange Wine and Shatterday, his previous major collections, had hardcover editions from Houghton Mifflin.) It contains three or four good recent stories, a few ghastly stories from the 1950s (scrupulous revision has merely thrown their ghastliness into high relief), and four personal essays of such wit, passion, or poignancy that they easily redeem the whole motley compilation.

Empiricist or supernaturalist? Where does Ellison stand? In a moving introductory fable ("Quiet Lies the Locust Tells"), the author's narrator declares, "I do not believe in Gods, but I ask God never to let Her (i.e., Ellison's elusive personification of all that cripples or destroys genuine creativity) discover a way of reading the inside of the people. If she ever finds a way to probe and drain the heart, or the head, then all hope will be lost." And the narrator concludes by confessing a weariness that, paradoxically, the early stories, laboring under their genre trappings, illustrate far better than the half- despairing but vigorous later stories in which Ellison makes existential stoicism his watchword. Or does he? This is a man who deliberately thumbs his nose at labels.

Ellison's up side gets play in the essay "Saturn, November 11th," which celebrates the triumph of the Voyager I mission in 1980, the formidable significance of this event, and the author's own involvement as "an eyewitness to history." The images sent back from Saturn placed everyone at the Jet Propulsion Lab in Pasadena in the fictional territory of the novel version of 2001: A Space Odyssey. (For various technical considerations the film moved the action to the moons of Jupiter, and Clarke, for consistency's sake, has followed suit in 2010: Odyssey Two.) These images were real, however, and the unexpected and mechanically unaccountable braiding of the planet's rings tied the conventional scientific wisdom of the astronomers into knots. As Ellison puts it in this delightful piece, "The celestial engineer has been cutting capers again."

When NASA officials discover that a moon postulated by a French astronomer in 1966 does not in fact exist, Ellison gloats: "I am not a science fiction writer, no matter how my work is mislabeled by anal-retentive pigeonholers; I have written so few stories that required a scientific education that I have nothing to apologize for." Stalking the Nightmare confirms this persnickety observation. Insofar as subject matter goes, "Saturn, November 11th" is atypical Ellison. It is representative, however, in that it shows a concern for minute and gritty documentation that appears even in the bleakest of the contes cruels elsewhere in this collection. In the stories optimism gives way to angst (with two or three exceptions), and the "celestial engineer" of this essay steps aside for demons, irreverent magi, hideous ghouls, troublesome jinn, and the unappeasable Eumenides of loneliness. Ellison's religion, if he has one, is survival with dignity.

"Grail," a phantasmagoric account of one man's search for True Love, is the best story in the book. As the reader discovers in an Ellisonian footnote to the foreword by Stephen King, "Grail" was almost left out in favor of a story originally published in the April 1957 issue of Super-Science Fiction. Because the cruelest contes in this collection are pseudo-science-fiction yarns that should have been permitted to molder in the pulps ("Blank . . .," "Visionary," "Invasion Footnote," "Final Trophy," "Transcending Destiny," and "Tracking Level," to cite the cruelest), I am extremely grateful to Ellison for his decision to substitute "Grail" for the ironically entitled "Invulnerable." The substitution is a mature parable, vintage 1981, and its theme transcends the fashions of the moment.

Like "Grail," Tomorrow's Eve by Mathias Villiers de l'Isle-Adam, ably translated and introduced by Robert Martin Adams, professor emeritus of English at UCLA, obsessively glosses one man's search for True Love, in this case the young English lord Celian Ewald. Further, like Clarke's Odyssey novels, it brings the apparatus of the scientific method to bear on a question that is fundamentally spiritual. Thomas Edison--"The Sorcerer of Menlo Park" -- creates a perfect artificial replica of a beautiful young woman with whom Lord Ewald has fallen in love. He does so because Miss Alicia Clary, whose stunning physical features have sabotaged the nobleman's ability to attach his love to any other female image, has a soul of the utmost vulgarity and self-serving conventionality. Edison seeks to solve the problem by giving his replica a soul, an animating spirit, of unparalleled subtlety and distinction. Moreover, he succeeds.

Empiricist or supernaturalist? A bohemian in his life style but a staunch conservative Catholic in his faith and politics, Villiers wrote Tomorrow's Eve as an indignant satire on the secular positivism of Auguste Comte. First published in serial form in 1885-86 (while the real Edison was in his late thirties), the novel sought to demonstrate the bankruptcy of any philosophical system that accounted for the achievements and character of humanity solely in mechanistic terms. In many ways, in fact, Tomorrow's Eve anticipates, and attempts to refute, the behaviorist position of B.F. Skinner and the sociobiological approach of Edward O. Wilson. As Adams notes in his introduction, beleaguered Christians in the 19th century often cultivated a "mystical streak" as a counter to what they perceived as the deadening materialism he of their era.

Villiers is best known both here and abroad for Contes Cruels and the closet drama Axel. However, in spite of its occasional cranky jeremiads and its frequent soporific lapses into pseudo-scientific argle-bargle, Tomorrow's Eve does have its moments. I only wish they were closer together. The academic prose of the introduction is far more amusing than the novel itself, which has aged badly, and perhaps Adams, the translator, would have been better advised to prepare a coherent abridgment. It is hard to imagine anyone but graduate students or a few unaffiliated masochists reading the entire text of this novel. Still, Villiers is a witty epigrammatist (if not an altogether skillful storyteller), and maybe it would be good to conclude this review with an epigram that has at least indirect application to all three works under consideration here:

"Every man bears the name of Prometheus without knowing it--and none escapes the beak of the vulture."