We are led to believe, at the opening of this marvelously inventive work, that we are reflecting the poignant personal reminiscences of a Nobel prize-winning medical researcher, Dr. Harry Wolper, after his career is over and his life nearly so.

We soon realize something is amiss when the doctor tells us the moment he chose to become a scientist: after having viewed Spencer Tracy raising a smoking, foaming test tube to his lips to transform himself from Dr. Jekyll to Mr. Hyde. Dr. Wolper, who is writing in diary form, also confesses to performing hundreds, maybe thousands of illegal abortions. As if to confirm his growing madness, Wolper cuts up his two pet frogs for no apparent reason, and discusses their insides.

After a month-and-a-half of diary entries, Dr. Wolper, although he is 69 years old and practically dead, decides to undertake the two most difficult chores of his life: writing a long philosophical novel and cloning his dead wife from a bit of her hand that he has saved in a jar.

Dr. Wolper turns out to be an inept Frankenstein, however, and struggles through the rest of his diary with the multiple monsters of his creation. Boris, the chief character of his novel rebels and begins to negotiate with Wolper for a better fictional space to inhabit. The beloved wife, resting comfortably as a string of molecules on the sugar lattice of life, proves reluctant to be coaxed into the world again. And Dr. Wolper's only natural creation, his son Arnold, turns out to be a blackmailer who has chosen his father as his victim.

Circling like a carousel, the diary entries spin out alternately chapters of the doctor's novel, skits, essays on the Fourth of July and scenes of the mad Dr. Wolper playing with eggs and seeds, growing deformed fetuses and trying to recall his wife from her purely informational form.

There are delightful parodies of transactions in a hospital, a courtroom and a psychiatrist's office. Leven toys with all the planes of reality possible when his novel-inside-the-novel begins to bleed out of its chapters to affect the action in other parts of the diary. This play ends with the last few lines of the book, when Levin makes it possible for us to believe that Boris is actually the Frankenstein, and Wolper his monstrous creation.

But for all the inventiveness, charming vignettes and Chinese box tricks, this book has serious defects, not the least of which is that it is 200 pages too long.

"As a general rule." Sydney Smith once wrote, "run your pen through every other word you have written; you have no idea what vigor it will give your style." In Leven's case, Smith might have added: In addition, run your pen through every other paragraph, and every other chapter as well; the result will be positively uplifting.

Perhaps because this is a first novel, Leven has dragged down from the attic all those fond objects he's recorded carefully in his notebooks -- the old shoe trees, the lace doilies, the great old credenza. A hundred pages of corny philosophy would have worked better in a page or two. At one point Leven even seems to abandon the pretense of a story: Near the end of the book there are six pages of nothing but favorite quotations and song lyrics.

Leven intended his book to be a philosophical novel; "I intended to comment on philosophy." he says through Boris at one point, ". . . one Giant Theme and one Giant Philosopher." But instead of a philosophical novel, he has a work in which characters name-drop and speak existentialese to one another. Apparently Leven could not figure out how to do what is necessary in fiction to create characters that embody philosophy, not spout it. n

Leven's intentions and inventions deserve more careful handlings, but, still, he's made a good start. If only his characters can reform him a little -- get him to clean up the metaphysical junk, to shorten their run to something less than marathon distance -- then they might put on for their author a performance that is not only clever, but rebust and effective as well.