Air Force Regulation 35-99 deals with the Personnel Reliability Program. It is a long document, more than 40 pages, laying out the regulations for "screening, selecting and continuously evaluating all personnel who control, handle, have access to, control the launch of, or control entry to, nuclear weapons or nuclear weapon systems."

The PRP program requires those with hands on nuclear weapons, from teen-aged technicians to four-star generals, to monitor their own moods and report on the moods of their buddies. They are required to take themselves away from the weapons when they are fighting with their spouses or taking antihistamines and to report their work mates for various other kinds of suspicious behavior.

These behavior flaws, listed in Section 2, Paragraph 3, include lack of humor, excessive talking, decreased talking, daydreaming, sleepwalking, unusual happiness and unusual sadness.

It is an eminently reasonable document to have in a world capable of suicide. In fact, it deals with suicide. It frowns on it, particularly for those who have access to nuclear weapons.

Suicide comes under subparagraph IV called "Factors Related to Mood and Feeling."

It says, "Suicide: Particularly significant when accomplished through the deliberate detonation of a weapon or crashing of an airplane." It goes on to say that this "may represent significant emotional disorder and require medical evaluation."

The behavioral section of the PRP regulations has a footnote.

It says, "NOTE: The presence of one or more of these behavior and personality factors does not necessarily mean that an individual is a reliability risk . . . . In cases of doubt, a medical evaluation is appropriate."

Yossarian, the central character in the novel "Catch-22," would have loved that one. Yossarian flew B25s in the Second World War. He was scared. He wanted out, and decided the only way was to tell the doctors he was insane.

Why do you think you are insane, Yossarian? Because I don't want to fly anymore. But it's insane to want to fly into flak and Messerschmidts, Yossarian. It is? Of course. Then why am I doing it? Because you're sane, Yossarian. You mean that it's insane to do what I'm doing and because I think it's insane I must be sane? That's right, Yossarian. And you won't ground me? Catch-22, Yossarian.

Of course, that was fiction.

An outsider entering the world that has taken us all to the crater's edge inevitably seeks an answer. Such is human nature. It becomes, in a way, a search for the Holy Grail.

Toward the end of the search, I took an hour-long train ride from Grand Central Station in Manhattan up the placid and serene Hudson River, passing in mind through the concentric circles of the blast effects on the nation's premier city, through the fireball and vaporization circle, the firestorm circle, the 300-mph-winds circle, onward up the shimmering river to a place where the winds might be no worse than those of a bad storm.

There, at a little village called Croton-on-Hudson, I found Herman Kahn. He is an immense man, his girth overlapping many circles, and a man with an immense intellect, albeit not always a comforting intellect. He has written books called "On Thermonuclear War" and "Thinking About the Unthinkable." He has studied the use of nuclear weapons in Korea and Vietnam. He says he thinks the use of nuclear weapons is immoral. He says he thinks they will be used.

Kahn speaks colorfully. He once was reported to have said that if a two-headed baby was born you got twice as much. "I never said that and I wouldn't," he told me. "But I said something that was close to that. If you want to criticize me, I say things remarkably close to that."

Kahn once went out to Strategic Air Command headquarters in Omaha, where the walls are papered with the motto, "Peace . . . Is Our Profession." The signs were down, temporarily, for the painters. "So I said, gee, I'm delighted that war is your profession. It's time you guys found out." He said the generals he was advising greeted his joke with "absolute dead silence." In a world of deterrence, he was undeterred.

"You guys don't have a war plan," he told the generals. "You've got a war orgasm."

Kahn agreed that MAD, the policy of Mutually Assured Destruction, was mad. "Use the word orgasm," he said, adding that it was a male orgasm at that. "That's the usual image of nuclear war: press every button in the house and go home." That image, he said, is "dead wrong" as a probability or a policy.

Kahn was equally unimpressed with NUTS, the contrived acronym meaning Nuclear Utilization Target Selection, for a policy of limited nuclear wars, talk of which has helped bring the Bomb raging back into the public consciousness in the '80s.

But he had different reasons. Limited nuclear wars, as a policy contingency, are old hat. He was willing to bet, giving odds of 100 to 1, that the Soviets would not have responded if the United States had used tactical nuclear weapons in Vietnam. But we had no targets there, he said, and it was immoral.

The biggest problem, Kahn said, is that we are not planning for a protracted nuclear war. That worries him, Kahn says, and he says he does not worry much. "Even if you could control the war for just 10 to 20 hours, you've done a lot," Kahn said. He says he does not think we could.

He talked about psychic numbing and how it affected strategists as well as the public.

"You've got to be detached, no question about that. I know of no analyst who uses the term megadeath. The peace people use it and they think we use it. But the criticism is basically right. We don't look at those millions of numbers and try to visualize each baby, each 5-year-old kid. We don't go around saying there are 300,000 babies, 250,000 5-year-olds. You don't want to have a super imagination."

Finally, I asked him about the Holy Grail, the answer. His mood seemed to change. His voice shifted into lower gear, and the jovial, black humor of a man who has chosen to look at neutered millions disappeared.

"There is no Holy Grail," he said, his words both a challenge and a final statement. That, he said, is the trouble with the world of the '80s, looking for an easy answer. "Now we're looking for the first time at the final solution, and there are no final solutions. Up till now you've been a sensible, reasonable guy. You want an answer, go to your local church." There is no answer.

For seven years Roger Molander looked at the millions of numbers. He did not visualize each baby, each 5-year-old kid. He did his work in the sanctum of the National Security Council, well inside the inner circle, at ground zero in the White House.

The longer he stayed, the less secure he felt. Policy makers were coming to him for answers. He had none. He saw that the men who made the decisions knew no more than he did, in fact counted on him for the answers. One day, during the never-ending hubbub and relentless in-fighting of the White House, he asked himself the same question a colleague had asked him: "Where are all the grownups?"

Molander left, although he didn't go far from the real inner circle. He moved a few blocks away, to a less-prestigious office on 15th Street, still well within the circle of probable error of a missile aimed at the White House. He formed an organization called Ground Zero in an effort to educate people about nuclear war.

I asked him about the Holy Grail. It is one thing to worry about our lives, our children's lives, the next year, the next decade or two decades. But how can this incredibly fragile system stay under control for 100 years, for 500? Molander said no one had ever asked him that question.

Life was going well for Molander in his new role. People were listening. But he seemed depressed. Who are the philosopher kings? I asked. Who can unravel the dilemma?

"There are no philosopher kings," he said.

Larry Smith, an extremely sensitive and bright man who spent years hearing and learning the arcane logic of the nuclear-arms world as a staff aide on the Senate Armed Services Committee, still looks into the maze of contradictions and danger each day. He sees no answers.

"Freddie the Flam up on Ward Seven has as good a view of this as CINCSAC," Smith said. CINCSAC is the commanding general of the Strategic Air Command.

A few years ago, about the time that SALT II was in its death throes, victim of election-year politics and the "discovery" of a 3,000-man Soviet brigade in Cuba that had been there for years, I visited the world of PRP and MAD at Malmstrom Air Force Base in Great Falls, Mont.

While there, I met a young Minuteman missile repairman named John Brewer. Brewer's job was to go down into the silos that circle Great Falls and fix the giant symbols of security, each with a megaton atop it, whenever one malfunctioned. Brewer's fingernails were chewed halfway to the cuticles.

The SAC commanders at Malmstrom were aflutter the day of the visit. They had found marijuana cigarette butts inside the top-security compound of a Minuteman command capsule and had traced them to the installation's guards. Someone inside the base had leaked the story to the Great Falls newspaper. The story was brief, it not being the first incident.

Air Force Regulation 35-99 frowns on drug use. The regs warn that it "may cause loss of inhibitions, poor judgment or physical impairment."

Bill Arkin, who spent four years as a young Army intelligence officer in Berlin and now studies the arms race for the Institute for Policy Studies here, says he thinks drug use is a serious problem in the American military. But he says he views it as a given, and is always fascinated when we "discover" drug use aboard military vessels, during plane crashes or around nuclear weapons.

Arkin's fascination turns to perplexion, however, when he sees how drug use is cranked into the strategists' equations of the relative reliability and strength of American and Soviet forces. He says it is one of the many ways that the strategists "quantify" the strategic balance, finding America lacking and the Soviets superior. The strategists can't quantify an equivalent problem on the other side, he says, so they ignore it.

Arkin says Soviet military forces, including those around nuclear weapons, suffer from a "severe problem" with alcoholism.

If a person with a completely blank but comprehending mind--the proverbial man from Mars or the totally insulated Peter Sellers character in the film "Being There"--were to arrive in our midst today, he surely would be more perplexed than Bill Arkin or even the fictional Yossarian.

He would find children at a school in Tuscon with a Titan missile in their back yard to protect them. The children do evacuation drills regularly, not because they are afraid of the millions of tons of explosives that are aimed at them in some far-off hole along the Trans-Siberian Railroad. They are afraid their own missile, with 9 million tons of destruction atop it, will explode.

He would find the world's wisest men working at Strategic Arms Limitation Talks. When the first limitation was signed, the United States had 3,000 strategic warheads. When the second limitatation was signed, but not approved, the United States had 9,000 warheads. He would see that, by 1985, under the aegis of the unratified treaty, the United States is expected to have 18,000 warheads. He would find that the Soviets had expanded further, during the limitations.

He would see a planet that evolved slowly, in its latest inhabitants' view of time, and allowed those inhabitants aboard only as it methodically created natural systems to protect them from radiation. He would see the inhabitants reintroducing radiation to the world at a speed measured in planetary microseconds.

He would find that plutonium, a deadly man-made material with a radioactive half-life of 25,000 years, has been stored in cannisters with a full life of 20 years.

He would find a planet on which intelligent and well-meaning people see a world so dangerous that they must hold on to the means of its destruction until human nature stabilizes. And a planet on which equally intelligent and well-meaning people see a world so dangerous that they must rid it of the means of its destruction until human nature stabilizes.

He would find great nations leading the way in accumulation of the destructive power, small nations scrambling to get into the act. He would find almost no one, among the wisest and the closest to the dilemma, who don't think the weapons will be used in the near future.

He would find it very strange being there, this man with a comprehending but totally blank mind uncluttered by tribal rivalries and human rationalizations.

Roger Molander, sitting in his Ground Zero office in the ground zero circle, tries to look differently at the world and finds it difficult. He says he fully expects bombs to go off in his lifetime because there are no grown-ups around. He says he sees only two real possibilities for the world, one difficult and unlikely, one far more easy and likely.

The difficult one, he says, involves "finding an Anwar Sadat," a nuclear-age visionary who lays all risk aside except the greatest risk. It is a long shot, requiring luck and the "tremendous coincidence" of actually finding two of them simultaneously and soon, one in the United States and one in the Soviet Union.

The second possibility, he says, is that "there be one more nuclear war." His vision of that possibility has two variations.

"In one we would be very lucky and it would be a very short, very small nuclear war. Somebody like India and Pakistan will lob a couple at each other and, if we're lucky, it will stop there."

Then, Molander says, if the world is still lucky, "We will look at the holes in the ground, the millions dead, and the horror will bring us to our senses for another 50 years or so." He doesn't wish such a thing on the Pakistanis and Indians, but his other variation is not so lucky for anyone.

"The other is that it will expand into the full confrontation, bringing in the Americans and the Soviets, and then the southern hemisphere will start remaking the world because the northern hemisphere won't be worth living in anymore." In his down moments, Molander thinks the second possibility is the likely one.

At Croton-on-Hudson, Kahn has a slightly brighter view. He, too, says he thinks the bombs will go off. He, too, says it is more likely to occur between the emerging nuclear nations, of which the count may be almost 20 by the year 2,000. But he says he thinks it is survivable, that the very worst is survivable.

The worst is unrestrained nuclear war between the two nuclear superpowers. The danger of that, Kahn said, is greatest in the next 20 years, as the United States and the Soviet Union decline in relative power to other nations. But Kahn says he is convinced that "you can survive a very massive nuclear war, and that's the least likely war out of the group."

The problem today, says the man who wrote "Thinking About the Unthinkable" 20 years ago, is that people are talking about the unthinkable but not thinking it through. He is referring specifically to the Physicians for Social Responsibility, an anti-nuclear doctors' group that is criss-crossing the country with warnings that nuclear war could be "the final epidemic," with a thousand Hiroshimas and no doctors, no help, coming in from the outside.

"They don't have enough blood plasma," Kahn said. "Come on. Of all the problems you've got, that ain't the problem. They focus with loving care on the silly."

But Kahn's difference with Molander, as each attempts to look at a possible future of man-made suns igniting on earth, may be a difference of semantics, a difference in the meaning of survival, a difference as bizarre as the nuclear world in which we live.

Question: What are the real problems?

Kahn: The unexpected effects, things you don't know. It's not as bad you think. If you destroy the ozone layer which protects the earth from solar radiation , you're going to go around with coverings like they do in the deserts. And there'll be no change in human health. What it does to animals and vegetables is a complicated story. But human beings? I won't like it. I don't wear hats. I like convertibles. But it's not a problem. It's just uncomfortable.

Question: Well, we'd have severe problems, obviously. You're saying there would be people surviving.

Kahn: No, I'm saying there'd be very few problems of human health. They are problems of human discomfort.

Question: How long?

Kahn: As long as it takes to rebuild, and that could be anywhere from a few months to 30 years. We don't know.

That's the worst, according to Kahn. By the 21st century Kahn sees at least seven superpowers, all with significant gross national products, all likely to have major nuclear arsenals. This would build a new quotient of fear into international politics, and Kahn sees security in that fear. If two of the superpowers went after each other with nuclear weapons, the others would inherit the power.

The quotient of fear is high.

Michael Carey, a former assistant to the nuclear-activist psychiatrist Robert Lifton, studied the evolution of the fears of elementary schoolchildren of the '50s, those kids who learned the nuclear crouch beneath their small desks. He found that at first they felt "absolute terror" and "fantasies of total destruction involving family, parents, oneself." Later, they learned to cope, or suppress.

By the time these children, now in their 30s, grew to early adulthood "all kinds of dreams and fears" recurred, often only slightly above the level of the subconscious. They felt a fear of "collective annihilation" and finally a "sense of absurdity" about the world in which they lived, a Yossarian sense. To the people Carey studied, Lifton writes, "combatting the bomb seemed crazy; the authorities seemed crazy, the world seemed crazy." They were afraid, although often they suppressed the fear.

Many kinds of fear are abroad.

Larry Smith says he is more afraid of the politicians and the theorists than of the generals and admirals. The generals and admirals didn't build the weapons, he says, and they are required to touch them every day in No Lone Zones, maybe use them. He thinks they have greater respect for the dilemma than the men who play with numbers.

Molander, after seven years in the NSC, has no sympathy for the Soviets. "What can you say about them?" he asks. "They're bastards." But he can understand their fear. Every country in the world that has nuclear weapons has them pointed at the Soviets, he says. Paranoia comes easily.

Kahn says he is afraid of American arms negotiators because they are more afraid of the arms race than they are of the Soviets.

Albert Einstein--the mild-mannered genius who gave us the dilemma by discovering that mass was energy locked up and, unlocked, would explode outward at the speed of light--was afraid. "In the end," he said as men prepared to step beyond the atom bomb to the hydrogen bomb, "there beckons more and more clearly general annihilation."

World government was the utopian answer fashionable among some after the new power was unleashed 37 years ago. Einstein said he feared the tyranny of world government but feared the coming of a nuclear war more.

Jonathan Schell, in his book "The Fate of the Earth," methodically constructed all the possible horrors of a nuclear war, including destruction of the ozone layer, creation of a new ice age and Einstein's fear of general annihilation, the end of the species.

Just as methodically, Schell dismantled some of the escapist fantasies of which men have dreamed. Total disarmament? Einstein's secret doesn't go away. E=mc2 is here to stay, the methodology there to rebuild dismantled bombs. Escape to other planets, we brilliant technicians who can discover and build but not yet deal and solve? E=mc2 would go with us.

So Schell, in grasping for the Grail, came back to the answer of world government, which seems further out of reach than the universe.

Schell was "grappling with infinity," Kahn says. "What do you do when you have infinity in the equation? You can't bounce anything against infinity--half of infinity is infinity, a tenth of infinity is infinity."

Molander was flying out of New York shortly after Schell's book appeared in a series of articles in The New Yorker. On the same flight was one of his old colleagues, a man who had served in the highest levels of government and had spent his life dealing with the nuclear dilemma.

His old colleague was complaining that the fallacy in Schell's answer was that it required "a quantum change in human nature." Perhaps in 500 years, the arms expert said, and perhaps in 500 years we'll colonize Mars.

Molander recalls staring out the aircraft window, thinking how far he had moved from one ground zero to another. He wasn't sure he disagreed with his old colleague's pragmatic view of human nature. He still didn't have the answer. But he wondered if that quantum leap might be where the grownups are. He wondered whether we had 500 years "when we've got kids who don't think our ways are going to buy them 10 or 20 years."

Five hundred years is a long time at the crater's edge, infinity too long. Shortly after the bombs were dropped on Hiroshima and Nagasaki, Time magazine asked an 8-year-old boy what he wanted to be when he grew up.

Alive, the boy replied.

At Cal Tech in Pasadena, where Kahn first got into his business and where a new generation of nuclear physicists comes out into the real world each year, Steve Trentalange of Waterbury, Conn., sat talking about his prospective career. He is 27 and has spent 10 years seeking the doctorate in nuclear physics that will be his this spring.

Trentalange has been a "scientist" since he was 8, when he became interested in chemistry and then dinosaur eggs others found in the Gobi Desert. His childhood quest took him inevitably into the secrets of the atom.

In science the mystery of the atom is romantic and compelling, the mystery infinite. Trentalange understands the drama that drew his predecessors into the Manhattan Project, into the challenge in another remote desert similar to the one that yielded the dinosaur eggs that entranced him as a child. And he understands the magnetic pull of the search into infinity that drew them then to Trinity near the McDonald ranch house in the valley known as the Journey of the Dead.

He is job-hunting. The government and the national laboratories, or corporations that serve them, provide most of the jobs, much of it in weapons-related work.

Trentalange says he thinks he will go into teaching.