ONE ALWAYS wonders when a posthumous work appears on the market just what there was about it that the creator did not want seen while he was alive. Jimi Hendrix, for example, undoubtedly put out more albums after his death than before. In the case of Philip K. Dick's fine Radio Free Albemuth (Arbor House, $14.95), the answer may be simply that Dick might well have written this work as an act of catharsis. Although it contains all of the paranoia and bizarreness taken for granted in a novel by Dick, there are decidedly unique elements.

For one thing, the narrator through the majority of the book is Philip K. Dick himself. The world is ours in the 1970s, only it seems that back after Lyndon Johnson, the next president was a man named Ferris Fremont. Not a very compelling politician himself, Fremont engineered the assassinations of the Kennedys, of Bishop Pike, and very likely of Richard Nixon himself since the implication is that all other contenders had to be eliminated in order for FF to win. Freemont is also a sleeper agent for the Soviet Union (while publicly embracing the view of what we know as the right wing), and has turned the United States into a Nazi-like state.

Combatting this evil is an extraterrestrial god called Valis, which many readers will recognize from the novel of that name. In fact, the plots of Radio Free Albemuth and Valis are very similar. Of the two, the first is far more terrifying, because Dick the narrator constantly shows you how normal life is except for these other elements, these monsters in disguise who can come and get you any time they want.

More weight is added to the events described in Radio Free Albemuth by another Arbor House book, Only Apparently Real (Arbor House, $7.95), a collection of interviews with and observations on Philip K. Dick by Paul Williams. Somewhat fictionalized scenes from the novel unfold here in fact, the principal shared incident being the burglary of Dick's house by parties unknown, but parties who used government issue plastique explosives and stole canceled checks but not stereos. Dick's helpless terror and paranoia comes across, free of fictional trappings.

Dick was in fact a paranoid who rarely left his home and then hardly went more than a few blocks from it; who went through five marriages; who never in his lifetime received the recognition or remuneration he richly deserved while hacks all around him sailed high. Paul Williams' book leaves the lingering impression that Philip K. Dick lived much better and more rationally on paper than anywhere else. The insights into his novels are valuable and will, it can be hoped, open the way to more research on this superb, unique writer.

Kit Reed

ALREADY 1986 looks to be a remarkable year for the resurgence of the short story. A stellar collection from William Gibson is already out, and one from Lucius Shepard promises breathtaking prose later this year. Each of the 17 stories in Kit Reed's second collection, The Revenge of the Senior Citizens Plus (Doubleday, $12.95) offer something worth savoring. The opener, "Shan," is told in perfectly serious tones by a lonely woman who hangs out at Tupperware parties until one such party offers something unique, with hilarious results. "Chicken Soup" reveals a horrific, inescapable Oedipus complex. Then there's "In the Parlor," in which an aging woman tries to reassemble a room where childhood magic occurred -- a very poignant, painful story. Or "Frontier," where a man returns home to find his wife and children missing, but who performs a far worse eradication of them in his mind.

I could list each story and easily say something positive about it, because Reed is that good, her writing is a treasure house of gems. Here, from the title novella, is a simple description that opens the core of pain at the heart of old age: "She had . . . held hundreds of conversations with clerks in the various stores over products she had already forgotten, because she was grateful for the chance to hear herself talk."

Hard Tech

HUGO AWARD winner Timothy Zahn has a collection of stories out, too -- Cascade Point (Bluejay, $15.95). Zahn is what is referred to as an "idea" writer, that is his stories are often extrapolations from hard scientific data. The general weakness shared by most writers of this type of fiction is a blindness to good style and characterization. Zahn is no exception: his thin characters are most at ease when hotly debating theories, as in "The Energy Crisis of 2215," where, having harnessed a black hole as the ultimate means of supplying energy to earth, a team of scientists must find a way to keep it from heating up and exploding after they've tinkered with it. In "The Dreamsender," he comes up with in interesting notion -- that of a man who can put himself into a trance and pass into other people's dreams as an active participant. Unfortunately, this turns almost immediately into a detective story, which might easily have been written without the dreamsending angle at all. "The Cassandra" deals in a confused way with a planet colony that has been evacuated because all of the people on it have been infected by a virus that puts them in precognitive trances. It also apparently gives them white hair and green eyes, though for no accountable reason.

This is to say that, although every story of Zahn's contains a novel idea, none is handled in a particularly novel way. In some cases, as in the novella "Cascade Point," the pseudo-scientific gibberish drowns the reader. Witness this bit of climactic speech: "For the past two days we've been moving toward a position where the galactic field and other parameters are almost exactly the same as we had when we went through that point -- providing your neural tracer is on and we're heading back toward Taimyr. In another two days we'll turn around and get our velocity vector lined up correctly. Then, with your tracer running, we're going to fire up the generator and rotate the same amount -- by gyro reading -- as we did then." The speech lumbers on for another half page, and if it were the single example of such ghastly dialogue, it might be forgivable; but it's not. This story received the aforementioned Hugo award and one can only wonder at the reading tastes of the voting science fiction fans.

Kim Stanley Robinson

IN SHORT STORIES, though, I've saved the best for last. Certainly one of the finest stylists of fantastic literature going, Kim Stanley Robinson could write any kind of fiction he chose. The Planet on the Table (Tor, $14.95) will prove that to any perceptive reader. Here is an unbeatable collection, leading off with the subtle "Venice Drowned," where the citizens live in bell towers -- all that remains of Venice above the water line. From this we're introduced to "Mercurial," a mystery with a female Sherlock Holmes who is, among other things, utterly amoral. "Ridge Running" is a quiet story of haunting beauty. It might easily be a superb mainstream story from any magazine except that it hinges on a single scientific advance without which there's no story; in the truest sense, then, it is grand science fiction.

Another story -- "The Disguise" -- has buried in it original Jacobean drama, but as the play within the play unfolds so, too, does a character within the character -- for that's how parts are learned in this tale, by embedding, which itself becomes a metaphor with fearful implications. In "The Lucky Strike," the Enola Gay is disabled and another plane must fly over Hiroshima to drop the atomic bomb, but with unanticipated results. Last there is "Black Air," a Nebula Award winning story to take the breath away. Here a young Moroccan boy goes aboard a Spanish galleon, part of the "Most Fortunate Invincible Armada" that is about to assault the British Isles, where he will become a survivor of one of history's most remarkable sea disasters.

There are other stories, and each is rich storytelling. To anyone who appreciates good fiction, I recommend this collection most highly.Gregory Frost's most recent novel is "Tain." Its companion volume "Remscela" will be out next year.