February 18, 1986

ERIC LIEBLER allows his imagination to run freely. He has just hijacked a planeload of Americans to Sicily. ''I didn't intend to kill anyone,'' he says, ''but the American and Italian Governments didn't respond to my demands. I ended up shooting one passenger every five minutes.''

On the fourth floor of Mount Sinai Hospital is a cramped office crowded with shelves of computer printouts. Few patients get to see it. But it is a place at Mount Sinai where the search for scientific truth and the practice of medicine intersect; a room of graphs and charts and statistics where patients appear as tiny dots and lives are measured by the length of black lines. The patients on these charts are in the care of Dr. James F. Holland, who is trying to cure cancer. They are subjects of his experiments in a mutually agreed upon arrangement in which the doctor is seeking knowledge and the patients what they hope is their best chance to survive. Breakthroughs in Treatment It is an intricate bargain of unknowns because the experimental treatment may be as lethal as the cancer itself. At best, an experiment may save a life; at the other extreme, doctors say, the death of someone who was dying anyway contributed to knowledge of the disease.

''We feel the company can no longer guarantee the safety of capsules to a degree consistent with Johnson & Johnson's standards of responsibility to its consumers.'' -James E. Burke, the chairman of Johnson & Johnson. [ A1:4. ]

Donald H. Trautlein, chairman and chief executive of the Bethlehem Steel Corporation, will relinquish the chief executive's post to Walter F. Williams, the company's president, effective March 1, Mr. Trautlein announced yesterday. Mr. Trautlein, who will remain as chairman, said the board had approved the move, at his recommendation. ''I have completed nearly six years as chairman, and have put into place many of the plans and programs that I had hoped to establish,'' Mr. Trautlein said. ''It seems appropriate, therefore, to have Mr. Williams assume the chief executive officer reponsibility.''

Johnson & Johnson yesterday discontinued the manufacture and sale of all its over-the-counter medications in capsule form to prevent the kind of tampering that recently killed a woman who took cyanide-laced capsules of Extra-Strength Tylenol. The company also offered, at its expense, to replace about 15 million packages of its capsule products in stores and homes across the nation with caplets, which are oval-shaped tablets coated to make them easier to swallow. It said it hoped to rebuild the lost capsule market in less tamper-prone caplets and tablets. The phamaceutical concern, which markets scores of products and had sales of $6.4 billion last year, estimated that its withdrawal from capsules would cost $100 million to $150 million, after taxes. This will include the expenses of replacing six kinds of capsules already on the market and of retooling its plants, as well as other costs in trying to rebuild its market position.

After six years, the Afghan war has begun coming home. The outlines may be hazy - the size of the Soviet force, the scale of the fighting, the casualties and the Western reports of Soviet atrocities are not widely known here, or are dismissed as Western propaganda. Yet in conversations with Russians the war has become more familiar and tangible. Although the Soviet Union has made no statistics public, hundreds of thousands of Soviet youths, most of them draftees, are known to have gone and returned from the dusty and dangerous mountains to the south. Thousands have been wounded and killed. Some have returned crippled, some troubled.

Contrary to the Reagan Administration's goal of reducing Government regulation, Federal banking agencies have been moving toward more regulation and supervision of commercial banks and thrift institutions. Banking experts call the trend re-regulation and say it will continue for some time, as the industry struggles under its greatest strains in decades, chiefly brought about by loans for agriculture, energy, real estate and developing nations. The new wave of regulation does not, by all accounts, represent an ideological switch by the regulators. Rather, banking experts say, the Government has acted of necessity after a record number of liquidations and distress mergers in 1985.

For decades, there has been a mystique about the Inland Steel Company. It was thought to be a little more savvy and more technologically sophisticated than its domestic competitors. Even Japan's steelmaking elite -who rarely praise their stumbling competitors in the United States -have often spoken in respectful tones about Inland, which is based here and is the nation's fourth-largest steelmaker. But in recent times, Inland has come up against some powerful external forces: falling steel prices, weak demand and a strong surge of imports. In 1985, Inland had its fourth straight year of losses and its worst year ever - losing $178.4 million on sales of $3 billion. And for the first time in half a century, Inland skipped its dividend.

An already competitive battle for the huge market for pain relievers can only become more complicated after the latest Tylenol poisoning episode. Since the middle of 1984, a new type of non-prescription analgesic, ibuprofen, has been making major inroads, putting pressure on better-established products. The ibuprofen pain relievers - sold under the brand names Advil and Nuprin - have captured 9 percent of the $1.7 billion market. That is less, however, than the 15 to 20 percent market share some experts had expected when the product was introduced. But many industry experts predict that the drug's share will continue to grow, further squeezing aspirin and acetaminophen products, such as Tylenol. ''The companies are now beginning to gain the market shares anticipated after a slow start,'' said Ronald M. Nordmann, an analyst at Paine Webber.

MANY scientists are so sure that the sea level will rise visibly in the coming decades that they are advising planners to adopt new strategies now. A predicted rise in sea level of one foot within the next 30 to 40 years will drive much of the Atlantic and Gulf shoreline inward by a hundred feet and some of it by more than a thousand feet, according to marine geologists. The environmental and economic consequences will be felt much farther inland. The loss of land to the seas ''will create havoc on our shoreline,'' warned Orrin H. Pilkey, a marine geologist at Duke University. ''Americans have been rushing to the coast, but much of our beachfront development has been contemptuous of natural forces.'' Creeping waters will destroy buildings and roads, wipe out recreational beaches, escalate flood problems many miles inland, pollute community wells with saltwater and drown coastal marshes vital to fish and birds.

WATCH any childhood battlefield. Some children are fighting, others -maybe just one - may be trying to settle it. That child, the mediator and not the combatants, is likely to develop and use the skills that will lead to the exercise of influence and the possession of power in adult life. This observation, along with many others that now coincide with it, illustrates a new understanding of how and why some people go through life getting their way while others follow them. It is a skill that baffles the envious who watch them and wonder what the secret to this success could be. But it is far less baffling to psychologists who in current research have begun to outline some of the specific skills that a great many, if not all, persuasive people have, from Mahandas Gandhi, to the Rev. Dr. Martin Luther King Jr. to Franklin Delano Roosevelt. The pattern they describe, however, is not one that applies to others who sway people, sometimes ruthlessly, because of bestowed authority, such as dictators.

Let others clip supermarket coupons. These bargain hunters collect parking tickets. ''It's not that I enjoy getting tickets,'' said Suzanne Christina, who gets one every day. ''But the parking garage is just too expensive.''