CAN MACHINES THINK? THE HUMAN BODY IS A MAterial machine that accompanies consciousness [TECHNOLOGY, March 25], and it is conceivable that someday we can put together a machine that exactly duplicates the body, with structural details matching every fundamental particle. In the age of artificial hearts and babies born from long-frozen embryos, it is also conceivable that such a "machine" will act as a sentient being capable of experiencing life just as does a human. But does that diminish the mystery and glory of consciousness? Does it change its unique place in the fundamental scheme of things in this universe? Can we ever objectively solve the mystery of consciousness through consciousness? MANI L. BHAUMIK Los Angeles

YOU CANNOT KNOW IF A MACHINE THINKS until you define thought. One way to have a thinking machine is to invent a definition of thought that fits whatever it is that your machine does. Then, if this definition is too close to what humans do, you have only to invent another, safer definition of what humans do. This sort of deus ex machina should ease the philosophical anxiety surrounding the whole argument...I think. STAN SEARS Los Angeles

YOUR IMPLIED QUESTION "SO WHAT (IF anything) is special about the human mind?" is absurd. Unless, of course, you received some letters from machines critiquing your story. GEORGE J. GORDON Spokane, Washington

IT IS NOT A COMPUTER'S WINNING AT chess that disturbs me; a simple calculator can beat me at math. But when the computer sitting across from chess champion Garry Kasparov is instructed to play, and its screen reads, ''I'd rather not,'' then I'll start worrying about whether the next person I meet is a Terminator. Independent thought is the advantage we humans (currently) have over ''thinking'' machines. CLAY LOOMIS Arroyo Grande, California Via E-mail

IT IS NO SURPRISE THAT TODAY'S COMPUTers, which are made of electronic circuits, lack human feelings. Feelings are based on chemistry, not electronics. Even our moods can be influenced by chemicals, such as alcohol. It is difficult to disentangle the feeling of love from the physical attraction between opposite sexes, yet this attraction depends on the partners' hormonal makeup, which is the work of chemistry. In order to produce human feelings in computers there would have to be chemical reactions in the machines. KAZEM OMIDVAR Washington

TO SHOW WHAT COMPUTERS CANNOT DO, match one with a poet. If the machine has any intelligence, it will say nolo contendere. The computer should compete with Seamus Heaney, the Nobel laureate poet, not with a chess master like Kasparov. This doesn't mean that Heaney has a "soul" and the machine does not. It means that nature's thinkers--humans, with their art, humor and compassion--can be mimicked by science but never matched. Not now. Not ever. DANIEL C. MAGUIRE Milwaukee, Wisconsin

HOW UNFORTUNATE THAT A REPORT inspired by the chess-playing program of Deep Blue did not even bother to name IBM's Murray Campbell and Thomas Anantharaman, the scientists who were the program's authors. Artificial intelligence's other technical leaders were similarly ignored. When machines do think, it will be the scientists, not the showmen, who deserve the credit. MATTHEW GINSBERG Eugene, Oregon

TWINS CONJOINED FOR LIFE

I WORK IN THE FIELD OF DEVELOPMENTAL disabilities, and thought I had seen everything. Your story on the conjoined twins Abigail and Brittany Hensel [MEDICINE, March 25] certainly made me look at my life's problems in a different light. The politicians inside the Beltway could learn a lot from these two bright six-year-old girls. I wish the twins well. ROBERT A. GEBHARDT Plattsburgh, New York

HOW FORTUNATE FOR THE HENSEL TWINS to be in a loving family and an accepting community. Would that they continue to find such acceptance in the larger world, which is not notably receptive to people's differences. The twins' challenge will be to continue to focus on their abilities and not worry too much about their shortcomings. Since this is the same challenge facing everyone else, they should be able to count themselves as normal individuals indeed. JAMES C. PLUNTZE Olympia, Washington

PATTY AND MIKE HENSEL'S UNRESERVED love for their abnormal six-year-olds contrasts reassuringly with killer Thomas Hamilton's eruption of hate on the youngsters of Dunblane. The world sorely needs that kind of contrast. JAMES A. DUNLOP Northfield, Minnesota

INNOCENTS CAUGHT IN HARM'S WAY

DUNBLANE, SCOTLAND, HAS OVERFLOWED with tributes to its 16 murdered children [WORLD, March 25]. But let us also memorialize teacher Gwenne Mayor. In the face of dark and bloody chaos, she reached beyond duty and instinct into the best of her human self and staked her life to try to defend other people's children. That she was slain in this attempt, along with so many of her charges, in no way diminishes the fact that in the long run it is love like hers that will triumph. ANTHONY BUCKLAND North Vancouver, British Columbia

I AM AN AMERICAN WHO HAS LIVED IN Dunblane for the past 20 years. My three children all had their early schooling at Dunblane primary. This town has always been for me a kinder, gentler place than the Los Angeles I left. A massacre of schoolchildren, I've been told, is something you might expect in California, but never in Dunblane.

There are people all over this world like murderer Thomas Hamilton, who think they have a right to whatever they very much want, in his case the company of young boys, and who will use whatever means they possess to punish those who will not give them what they want. The hundreds of bouquets lining the road in front of the school and filling the cathedral and churches of Dunblane, and the phone calls and letters my wife and I have received, testify that all over this world there are also kinder, gentler people. That is very good to know, but Dunblane is my home and a good place to live and, though I've been told that I should, I'll not leave it. ROBERT CONLEY Dunblane, Scotland

YOUR COVERAGE OF THE TRAGEDY AT Dunblane was a sensitive and moving tribute to the grieving parents and friends of the dead. The genuine suffering of the victims makes me resent all the more the media's focusing so much attention on these murdered white, middle-class children while all but ignoring the equally unthinkable deaths of other youngsters: the street children of Rio de Janeiro, periodically murdered by authorities and vigilantes when their numbers grow too large; the child sex workers of Thailand and Indonesia, who die slow and painful deaths when they are infected with aids or addicted to drugs; the uncounted thousands of children of Rwanda, hacked to pieces for being Hutu or Tutsi. These children were murdered by monsters every bit as scary as the psychotic who killed the Dunblane children. But because there are no smiling school portraits of them to tug at our heartstrings, because they die in places far from Western attention, they die unmourned and unnoticed. KRISTEN MCDERMOTT Norcross, Georgia

SEEMINGLY PERPLEXED BY THE LACK OF A "monstrous cause" for such a "monstrous effect" as the slaughter of innocents in Dunblane, Lance Morrow [ESSAY, March 25] noted that "only the vocabulary of evil" could explain what happened there. But as long as social commentators feel they can justifiably use the term nonentity to refer to any human being, society will continue to be plagued by eruptions of violence like the one at Dunblane. BRUCE A. FRENCH Guilford, Connecticut Via E-mail

AS I VIEWED WITH ANGUISH THE CLASS picture of the children who were killed and wounded in Scotland, I wondered how someone who probably once looked very much like one of those innocent little boys in the photograph could turn into such a murderous beast. LYNDA M. WILLYARD Bridgewater, Nova Scotia

WHILE MORROW AND OTHERS ENGAGE IN analysis and sophistry trying to explain what happened at Dunblane, the most fundamental reason is clear: the monster Hamilton had four loaded handguns. Would the gun worshippers have us believe that this maniac could have achieved such a level of carnage with a sword or a bow and arrow? CHARLES ESTES Fullerton, California

SO THE FATHER OF THOMAS HAMILTON, 65-year-old Thomas Watt, "can't live with" what happened in Dunblane and thinks he brought a monster into the world. Rather than indulging in these self-absorbed histrionics, Watt should feel shame for abandoning his son when the boy was only 18 months old and for never taking a bit of interest in his child in the years since. Monsters do not spring fully formed from a mother's womb. They become what they are over many years and after many wrong decisions. Had Watt stayed to bring up his son--or at least showed some interest in the boy and man--that might have saved the lives of 16 innocent children. IAN A. DUDUMAN Penhold, Alberta

RIPPLE EFFECTS FOR CHINA

THE U.S. SHOULD NOT TRY TO CONTAIN OR appease China, the upstart superpower, without first exposing the latter's Achilles' heel [WORLD, March 25]. The overriding reason for Beijing's saber rattling during Taiwan's presidential election campaign is that China's leaders are scared of the ripple effect that Taiwan's march toward full-fledged democracy will have on its own 1.2 billion population. The masses, having seen Taiwan progress from a backward nation into a free, prosperous country, may demand to choose their own leaders through a similar election or a plebiscite on China's communist system. The only thing the U.S. should do now is to safeguard the democratization of Taiwan. Sooner or later, the desire for more political freedom will prevail in mainland China. JENNIFER WEN Sugar Land, Texas

IF CONTAINMENT AND APPEASEMENT won't work with China, what should Washington do? Why not try the Five Principles of Peaceful Coexistence, first initiated by Zhou Enlai in June 1954: "mutual respect, nonaggression, noninterference, mutual benefit and, finally, peaceful coexistence." WINBERG CHAI Professor of Political Science University of Wyoming Laramie, Wyoming

THOSE GOVERNMENT PAYMENTS

AFTER READING YOUR STORY ON CORPOrate welfare and government outlays that help support certain industries [BUSINESS, March 25], I can see we have business as usual in Washington. The overused "tax and spend" label has been too often assigned only to Democrats. I have always believed that both Republicans and Democrats want to spend too much of our tax revenues, but they want to spend the money on different things. One issue both parties agree on is that payments to Big Business must continue, because they do not want to bite the hand that feeds their campaign funds. We must have election-finance reform and we must have it now, or nothing will ever change. LYNN SCHURRER Stillwater, Minnesota

CONTRARY TO YOUR ARTICLE ON CONgressional efforts to cut back on subsidies for Big Business, the U.S. is not "spending billions" to support the U.S. shipbuilding industry. We unilaterally stopped subsidizing commercial shipbuilding 15 years ago. President Clinton and Congress have joined in enacting and implementing an innovative national shipbuilding program that enhances private-sector financing with federal loan guarantees, not direct subsidies like those enjoyed by foreign shipyards. It also deregulates old programs, converts defense shipbuilding to commercial, competitive construction and negotiates to lower foreign subsidies.

As a result, for the first time in more than 30 years, American shipyards are building commercial ships for export. Orders for American-made ships are increasing, supporting jobs for thousands of Americans. An industry vital to our national defense is being preserved. With regard to the merchant marine itself, the subsidy program you castigate served its purpose, but it will not be renewed. President Clinton has proposed a new approach, one that costs less, removes restrictions on American operators and promotes competition. A.J. HERBERGER, Administrator U.S. Department of Transportation Maritime Administration Washington

THE SHIPBUILDING AND MERCHANT-marine bill being considered in Washington will make available limited subsidy money for only a handful of vessels (approximately 50) that the Pentagon has deemed militarily useful in support of a major conflict. The amount you state--$3 million per vessel for a shipowner to make his vessel available to Uncle Sam in wartime--is a gross exaggeration of the funding being contemplated by Congress. Also, the vessel pictured in the photo accompanying your story, Nosac Ranger, was not constructed with subsidy money, nor have its owners ever received one penny of subsidy money from the U.S. government since the vessel entered U.S.-flag service in 1988. DANIEL D. SMITH, Manager Marine Department Pacific-Gulf Marine Inc. Gretna, Louisiana

AUTOS ON THE INTERNET

YOUR REPORT ON NEW WAYS TO BUY A car noted that there are several Internet and private services that contain sites that will help consumers [PERSONAL FINANCE, March 18]. One of the Websites you included is DealerNet, but you mistakenly reported that it costs $14,000 for a dealer to sign up for a home-page site. Actually, the rate is only $1,495. Also, we would like to point out that the DealerNet service has more than 30,000 pages of information containing details on 1,600 makes and models of 1996 vehicles, and more than 200,000 used vehicles dating back to 1977. Consumers can make side-by-side vehicle comparisons. PAUL GUTHRIE, Vice President Reynolds & Reynolds Dayton, Ohio