ETHICS MAN

Peter Singer's ideas on the ethical treatment of animals have made him the world's most influential living philosopher. He also thinks that it is sometimes right to kill newborn babies. Michael Specter met Princeton University's newly appointed professor of bioethics

IT HAS BEEN more than 10 years since the disaster at Hillsborough football stadium. Ninety-six football fans were crushed to death that afternoon; yet the final victim, 17-year-old Tony Bland, didn't actually die there - at least, not technically. He was trampled so badly that his chest caved in and his lungs collapsed. Cut off from its oxygen supply, his cerebral cortex was destroyed within minutes.

Four years later, this is how Lord Justice Hoffman described his condition: "Since April 15, 1989, Anthony Bland has been in a persistent vegetative state. He lies in Airedale General Hospital ... fed liquid food by a pump through a tube passing through his nose...His bladder is emptied through a catheter... Reflex movements in the throat cause him to vomit and dribble. Of all this ... Anthony Bland has no consciousness at all. The parts of his brain that provided him with consciousness have turned to fluid. The darkness and oblivion which descended at Hillsborough will never depart. His body is alive, but he has no life in the sense that even the most pitifully handicapped but conscious human being has a life. But the advances of modern medicine permit him to be kept in this state for years, even perhaps for decades."

The justices decided not to let that happen. When they ruled, on February 4, 1993, that doctors could remove the feeding tubes and let Bland die, Britain's highest court made a reasoned decision to kill an innocent human being. Many people were outraged, but the Australian ethicist Peter Singer was not among them; in fact, Singer has argued for many years that euthanasia and infanticide are obvious necessities of the modern world. He wrote that the court's decision reflected "major shifts deep in the bedrock of western ethics," because Bland's death represented the collapse of a 2,000-year-old system of values - one that had enshrined the sanctity of human life, no matter how compromised.

"The day had to come, just as the day had to come when Copernicus proved that the earth is not at the centre of the universe," Singer told me not long ago. We were flying from Melbourne, where he lived, to Sydney, where he was to present a paper at a conference on reproductive genetics. "It is ridiculous to pretend that the old ethics still make sense when plainly they do not."

Singer is a lean, rangy 53-year-old, with a broad forehead and a ring of hair around his balding head which shoots in wisps straight into the air. He has a rich, deep baritone voice, but he doesn't like to use it; his words were so often drowned out by the drone of the jet engines that I had to ask more than once if he would mind speaking up.

"The notion that human life is sacred just because it's human life is medieval," he continued, talking about the treatment of the hopelessly ill. "The person that used to be there is gone. It doesn't matter how sad it makes us. All I am saying is that it's time to stop pretending that the world is not the way we know it to be."

Peter Singer may be the most controversial philosopher alive; he is certainly among the most influential. And as he settles into his new job as Princeton University's first professor of bioethics, his unorthodox views are being debated in America and beyond more passionately than ever before. For nearly 30 years, Singer has written with great severity on subjects ranging from what people should put on their dinner plates each night to how they should spend their money or assess the value of human life. He is always relevant, but what he has to say often seems outrageous: Singer believes, for example, that a human's life is not necessarily more sacred than a dog's, and that it might be more compassionate to carry out medical experiments on hopelessly disabled, unconscious orphans than on perfectly healthy rats. Yet his books are far more popular than those of any other modern philosopher. Animal Liberation, which was first published in 1975, has sold 500,000 copies and is widely regarded as the touchstone of the animal rights movement. In 1979, he brought out Practical Ethics, which has sold more than 120,000 copies, making it the most successful philosophy text ever published by Cambridge University Press.

Singer laid out his brutally frank approach to ethics in his first major paper, "Famine, Affluence, and Morality", which has become required reading for thousands of university students. "As I write this in November 1971, people are dying in East Bengal from lack of food, shelter, and medical care," Singer's essay began. "The suffering and death that are occurring there now are not inevitable, not unavoidable." The problem, he explained, is a result of the moral blindness of rich human beings who are far too selfish to come to the aid of the poor.

Following in the tradition of the 18th-century moral philosopher William Godwin - who asked, famously, "What magic is there in the pronoun `my' to overturn the decisions of everlasting truth?" Singer argues that proximity means nothing when it comes to moral decisions, and that personal relationships don't mean much, either. Saving your daughter's life is a fine thing to do, for example, but it can never measure up to saving the lives of 10 strangers. If you were faced with the choice, Singer's ethics would require you to save the strangers. "It makes no moral difference whether the person I can help is a neighbour's child 10 yards from me or a Bengali whose name I shall never know, 10,000 miles away," he wrote in his essay. Singer believes we are obliged to give money away until our sacrifice is of "comparable moral importance" to the agony of people starving to death. "This would mean, of course," he continued, approvingly, "that one would reduce oneself to very near the material circumstances of a Bengali refugee."

Singer's views on animal rights are even bolder: he calls man's dominion over other animals a "speciesist" outrage that can properly be compared only to the pain and suffering "which resulted from the centuries of tyranny by white humans over black humans." For Singer, that "tyranny" is one of the central social issues of our age. Yet what has brought him infamy is his radical position on an even more compelling set of moral questions: how to cope with the borders between birth, life and death in an era when we are becoming technologically capable of controlling them all.

Singer's beliefs have led him to places where few others are willing to go. He has suggested, for example, that parents who give birth to a haemophiliac might be better off killing it, especially if they could replace that dead infant with one who would be "likely to have a better life."

Singer often complains, with justification, that his comments on such issues are exaggerated and taken out of context, so it might be best to let him present the argument himself: "When the death of a disabled infant will lead to the birth of another infant with a better prospect of a happy life, the total amount of happiness will be greater if the disabled infant is killed. The loss of happy life for the first infant is outweighed by the gain of a happier life for the second. Therefore, if killing the haemophiliac infant has no adverse effect on others, it would, according to the total view, be right to kill him."

Few people will ever consider infants replaceable in the way that they consider free-range chickens replaceable, and Singer knows that. Yet many of those who would never act on his conclusions still agree that if an infant really had no hope of happiness, death would be more merciful than a life governed by misery. Singer's philosophy is a contemporary version of utilitarianism, and its basic intellectual weaponry rests on a simple thought crafted by Jeremy Bentham in the 19th century: all sentient creatures have an interest in avoiding pain. Bentham lived in a newly industrial England - a place where six-year-olds worked, suffered and died in hellish factories owned by people who were becoming indescribably rich. He established the first, essential principle of his new philosophy with the formula "each to count for one and none for more than one"; in other words, the happiness of any one person is no more important than the happiness of another. It was a revolutionary idea, and in 1861 John Stuart Mill elaborated on it in Utilitarianism: humanity should strive for the greatest possible happiness for the greatest number of people.

Singer studied at Oxford with RM Hare - perhaps the most important 20th- century descendant of Bentham and Mill - and his philosophy is called preference-utilitarianism. It is a more nuanced version of what Mill had in mind, with personal preferences taking the place of happiness. Singer's thought is shaped by the assumption that the results of your behaviour should agree with the preferences of anyone whom your behaviour would affect. For Singer, killing is wrong because when you kill someone who wants to live you make it impossible for that person to fulfil his preferences. Obviously, if you kill somebody whose preferences don't have much chance of success - a severely disabled infant, for example, or somebody in an advanced stage of Alzheimer's disease - the moral equation becomes entirely different.

Singer uses the word "person" to refer to self-conscious creatures: animals often fit that definition, and many humans do not. So when Singer says that you are more likely to do moral harm by killing a healthy cow than by killing a severely handicapped infant, he means that the cow is more likely to anticipate pain and suffer from it than the child. Singer believes that even relatively dumb animals - a chicken, for instance, or a mouse - deserve to be protected from unnecessary pain. And the more an animal is able to suffer and understand its surroundings, the more consideration it ought to be given. But he also believes the opposite - that any animal that has no hope of becoming self-aware has no hope of becoming a person. This is the reasoning that permitted Singer to write, in words that are almost always quoted out of context to portray him as evil or irrational, "Killing a disabled infant is not morally equivalent to killing a person. Very often it is not wrong at all."

Singer relies on a principle he calls "equal consideration of interests" to acknowledge the differences among species while still valuing all of them. Equal consideration and equal rights are not the same, though. For Singer, consideration varies with the complexity of the creature. So he would not say that since neither a baby nor a kitten is a person it doesn't matter which one you rescue from a burning house. You ought to save the baby. But equal consideration is his version of the Golden Rule, and he uses it to question the traditional distinctions between humans and other animals.

You don't need to suffer from existential doubt to be miserable; the anguish of a pig that lives only to be confined and then butchered counts as suffering to Singer in just the same way that human anxiety does. Singer says, as did Bentham, that what matters is not whether an animal can reason or talk, but whether it can suffer. And if an animal can suffer we have no moral right to torture it for medical research or to slaughter it for supper. ("When the United States Defence Department finds that its use of beagles to test lethal gases has evoked a howl of protest and offers to use rats instead," he wrote in Animal Liberation, "I am not appeased.")

Singer has never been afraid to take pure reason and drive it over a cliff. He asks horrifying questions and then answers them in unexpected ways. If killing baby girls (painlessly, of course) makes sense for farmers in China, then why not kill them? If a pregnant woman has inconclusive results from screening, Singer doesn't see why she shouldn't carry the foetus to term. Then, if the baby is severely disabled and the parents prefer to kill it, they should be allowed to. That way there would be fewer needless abortions and more healthy babies. (If killing the child would cause the parents distress, however, Singer believes that it would be wrong.) "What I am saying is that those decisions can also be made when life hasn't really got going," he told me, "because there isn't a being, a person who leads that life."

As an ethicist, Singer addresses questions faced by any family that has been confronted with an elderly, sick or helpless relative. He is important for the same reason that he is alarming: unlike most of us, Singer is willing - even eager - to answer those questions in the most unpleasantly honest way. "To say that I believe Peter is wrong about most of what he says would be an understatement," says Norman Ford, a Catholic priest and the director of Melbourne's Caroline Chisolm Center for Health Ethics, who has known and admired Singer for years. "But at least he is willing to talk about what is on everybody's mind. He is not afraid to say, `These are the problems of our time. Now let's deal with them.' He is not up there on Olympus - he is in the marketplace. And for a philosopher that is rare."

Many of Singer's opponents are offended by his activism, though. George Pell, Archbishop of Melbourne, has called Singer "Herod's propaganda minister", and recently, in a particularly ill-informed series of editorials, the Wall Street Journal compared him to Martin Bormann, Hitler's ideological henchman. The attack was nothing new. Singer has been prevented from speaking at conferences in Germany, in Austria and even in Switzerland, where he was once assaulted by people who saw in his philosophy echoes of the Nazi view that some lives are worth living and others are not. "When I rose to speak, a section of the audience ... began to chant, `Singer raus! Singer raus!'" he wrote in 1991. "As I heard this chanted, in German... I had an overwhelming feeling that this was what it must have been like to attempt to reason against the rising tide of Nazism in the declining days of the Weimar Republic."

I WASN'T sure what to expect when, in May, I travelled to Melbourne to see the man who had for so many years caused such fury. Despite the strident certainty of his prose, he hadn't seemed like a priggish moralist when we talked on the telephone. One friend told me, though, that unless I wanted to provoke a confrontation it would be inappropriate to wear leather shoes around a man who wrote that our refusal to grant other animals moral equality is like saying that all human beings - even psychopaths and murderers - are superior to any dolphin or chimpanzee.

Singer had warned me that after such a long flight I would be good for little more than a walk, and when I got to my hotel and called him he suggested that we take one. He lived nearby, and said he'd come right over. I almost changed into sneakers, but it looked like rain, and I decided not to be ridiculous. I wondered if Singer would be lucid, articulate and cold in person - a kind of high-end automaton. (His 24-year-old daughter, Marion, told me that once when her mother was away from home for several months Singer prepared the same dinner of spicy Asian soup for himself nearly every night.)

Singer appeared within minutes. He turned out to be a genial man, eager to talk and happy to listen. He was dressed in brown corduroys (which he wore nearly every day I spent with him), a green ribbed sweater, and canvas shoes. Singer asked if I wanted lunch, and wondered how I felt about vegetarian food. It was clear that he was prepared to watch me eat a chicken sandwich if necessary, but we ended up in a tiny place that served delicious macrobiotic vegan casseroles with unpronounceable names.

Because I didn't want to discuss anything too controversial in our first encounter, I told Singer what a profound effect Animal Liberation had had on many of the people I'd spoken with before travelling to Australia. It had originated in 1973 as an unsolicited contribution to the New York Review of Books - the first of many pieces he would publish there. The article received so much attention that Singer expanded it into a book. I asked him if he had been surprised by its lasting impact.

"To be honest, I was somewhat disappointed," Singer told me, a slightly wistful tone creeping into his voice. "It's had effects around the margins, of course, but they have mostly been minor. When I wrote it, I really thought the book would change the world. I know it sounds a little grand now, but at the time the Sixties still existed for us. It looked as if real changes were possible, and I let myself believe that this would be one of them. All you have to do is walk around the corner to McDonald's to see how successful I have been."

It was hard for me to believe he felt that way. The book has been used by scores of organisations, including the aggressive and extremely visible People for the Ethical Treatment of Animals, which was created in its wake. And it remains influential: next spring, for the first time, Harvard Law School is offering a course on animal rights law, and Animal Liberation is on the syllabus.

Although Singer has been called a right-wing killer by his most frenzied and ignorant enemies, he is really more of an enlightenment liberal. (He has just completed a book that attempts to reclaim the legacy of Charles Darwin for the political Left.) He is intensely political, and he knows how to wield his renown; this is a philosopher who sat in a cage in the middle of Melbourne to publicise the plight of battery hens, who has often protested against circuses, and who was once arrested while trying to photograph sows confined on a pig farm owned by the Australian Prime Minister. In 1996, hobbled by compulsive honesty, he ran a spectacularly unsuccessful race as a Green candidate for the Australian Senate. Had he been elected, Singer told me, he was prepared to give up academia completely - and I sensed that he wouldn't have minded a bit. Instead, his tenured chair at Princeton will make it possible for him to become the most prominent bioethicist in America.

Singer didn't seek the job at Princeton but felt that he couldn't turn it down. In How Are We to Live?, his 1993 examination of ethics in an age of self-interest, Singer wrote, "In the United States today, the social fabric of society has decayed to the point at which there are grounds for fearing it has passed the point of no return." When I asked him why he thought it was worth bothering with the place if it was so far gone, he replied, "The alternatives are all too horrible to consider. I have to at least give it a try."

SINGER HAS never been reluctant to speak his mind. Born in Melbourne in 1946, he and his older sister, Joan, grew up in a prosperous, happy family. His father, Ernest, who died in 1982, was a successful importer of coffee and tea. The family rarely celebrated any Jewish holiday; even so, his parents were astonished when Peter told them that he had no intention of going through with his bar mitzvah, because he did not believe in God. "Maybe my father was a little bit disappointed, although he was not really religious," Singer told me. "But my mother was probably quite pleased. My mother didn't identify with the Jewish community at all."

At the University of Melbourne, Singer became interested in philosophy, but he found metaphysics dry. "You can get into discussions about `Is this a table in front of us?' for quite a while," he said, pointing to a coffee table in his living room. "But the ethical discussions and the political philosophy seemed to be a lot more relevant and interesting." Singer was at Oxford when the war in Vietnam and the American civil-rights movement made academic philo-sophy seem antiquated. "I did a thesis at Oxford on civil disobedience, using Vietnam and Northern Ireland as examples," he said. "I wanted to pursue ethics, but not at an academic and theoretical level."

At Oxford, Singer was surprised when he noticed that friends of his were not eating meat, and more surprised when they told him they were vegetarians for moral reasons. He had never given the issue much thought. But within weeks he and his wife decided that vegetarianism was the only ethical way to live. "When you start analysing it," Singer told me, "it's so clearly wrong to eat the flesh of other animals that we simply had no choice."

Critics say that his moral certainty is one of Singer's most significant flaws - that he is too demanding, too impersonal and too dismissive of the way people actually relate to one another. In its rawest form, Singer's philosophy condemns people for caring more about their families than about strangers. "People do have special relationships with their families, their communities and their countries," Alan Ryan, warden of New College, told me. Ryan has written extensively on John Stuart Mill and taught for many years at Princeton. "This is the standard equipment of humanity and most people in human history have seen nothing wrong with it. Singer is an interesting and important fellow, but I am afraid that human beings just aren't put together the way that he wishes they were." In Ryan's view, no moral philosophy that departs so fundamentally from such common sentiments could possibly make sense.

Other philosophers criticise Singer more for the logical consequences of his beliefs than for his refusal to acknowledge that emotion plays an essential role in the narrative of life. For example, if we could take an action today that would benefit many people in 3,000 years, Singer would tell us to do it. It wouldn't matter that we would never see the benefits - or that the action might even cause us some harm.

Yet predicting the long-term effects of something is like guessing how the winds passing over the Sahara this summer will affect the world's weather in 50 years. There will be an impact, but who could accurately assess it now? Often, acts that seem benevolent - such as providing aid to starving nations - can have unforeseen and disastrous results, causing warfare, corruption, and, ultimately, more starvation. Even Singer's laudable desire to reduce suffering in the present can be seen as a recipe for the ruin of the world economy. Colin McGinn, who is a professor of philo- sophy at Rutgers University, asks, "What if you took every penny you ever had and gave it to the poor of Africa, as he would have us do? What we would have is no economy, no ability to generate new wealth or help anybody."

Despite Singer's immense influence - and perhaps because of it - most academic philosophers do not consider him an original thinker. "In many ways, I think Singer is more of a politician than a philosopher," McGinn told me. "He is a practical man, not a theorist. Yet, when it comes to a broader impact, I would have to admit that he may be the most influential philosopher alive. Singer wants to get out there and change the world, and to a degree that is surprising he has already succeeded."

BY 1998, Princeton had been searching for its new Ira W DeCamp Professor of Bioethics for nearly a decade. In many respects, Singer was an obvious choice, but he was also a controversial one. The philosophy department wanted a theorist, and Singer specialises in applied ethics, focussing on the world outside the academy. The biology department was nervous about hiring anyone who might oppose experiments with animals. But the university wanted to hire a professor who could stimulate debate. So Princeton made an unusual decision: Singer wouldn't be a member of either department. Instead, he has been appointed solely to the university's Center for Human Values.

Princeton's leaders have been valiant in defending their new professor's right to say whatever he wants. Still, the school is reeling from the public reaction to its choice. Long before Singer even moved to America, the university was picketed by groups such as Not Dead Yet, whose leader, Diane Coleman, told me that Singer "was a public advocate of genocide, and the most dangerous man on earth".

There has also been dissent among Princeton officials. Not long ago, Steve Forbes, a Republican Presidential candidate, who is a member of Princeton's board of trustees, sent a sharply worded letter - which invoked the Nazi euthanasia programme - to the university's president, Harold Shapiro, urging him to rescind the appointment. Shapiro, who is also the chairman of President Clinton's National Bioethics Advisory Commission, told me that he would never attempt to do such a thing, and noted, pointedly, that the appointment should not have caught Forbes by surprise, since Princeton's board must approve the hiring of every tenured professor. Even so, Princeton was unprepared for the intensity of the protest that has accompanied the selection. The university has been forced to take elaborate measures to ensure Singer's safety; Shapiro has received death threats; a campus group has been established to protest against infanticide; and even the usually tame Princeton Alumni Weekly has printed letters such as the one from a member of the class of '38, which stated: "Nothing I have seen or heard epitomises the decline of Western civilisation so much as the hiring of Peter Singer to teach in the university's Center for Human Values."

WATCHING Peter Singer think is like staring at the shifting gears of a precision engine: when you ask him about something, no matter how contentious or complex it is, you can see him churning through the calculations needed to produce a response. Singer told me that heroin should be legal, since its "prohibition has done more harm than good", and that violations of seat-belt laws should be punished, because the consequences of traffic accidents place an unfair burden on society. I asked about one probable result of genetic research: the ability to grow - from embryonic stem cells - organs to be used solely for spare body parts. He agreed that it was a tricky area with possibilities for abuse, by which he meant that only rich people would be able to dip into a vault to retrieve, say, a spare liver or heart. But in principle he doesn't see the harm in it. "I wouldn't say it's intrinsically wrong," he told me. "Some people would just say, `Well, using a human being as a means for spare parts is wrong.' I am not there."

This sort of reasoning can seem both numbingly logical and excessively coarse. Take, for example, his view of charity. Singer has written that humans need to overcome their greed, but more than once, as we strolled along the streets of Melbourne and Sydney, I saw him walk past homeless beggars without giving them a glance. When I asked if that was difficult, he looked surprised. "Not at all," he said. "Maybe you just help them take themselves into oblivion for a while. I would much rather give where I am convinced that the money will be used for good." The logic is hard to deny, yet there was something strangely disquieting about the ease with which this man - who, in the words of the British philosopher Bernard Williams, "is always so keen to mortify himself and tell everyone how to live" - could walk by people who were so desperately in need.

Despite Singer's often inflexible rhetoric, he acknowledges the gap between what he writes and how people live. "I think the point of espousing a theory is to say, `Look, if you're really going to be serious about ethics, well, here's a proposal as to how far you ought to go. Now, tell me why that's wrong,'" he said. "And if someone answers, `Well, nobody's going to do it,' I don't think that's an answer."

On the other hand, Singer tries not to be "rabbinical" about his beliefs. He no longer minds having dinner with people who order steak, and when I asked his thoughts about a recent operation in which surgeons implanted the aorta of a cow in a 13-month-old boy he said that if it was genuinely a choice between the cow and the boy they should save the boy. "If they are killing a million cows a day for dinner," he said dryly, "it's hard to make the case that we shouldn't use one to save a young boy's life."

Singer has recently published Ethics Into Action, which is in many ways his most personal book. It is a biography of the American animal-rights activist Henry Spira, who was extraordinarily effective because he never behaved so radically that people could dismiss him as a kook. Almost single-handedly, Spira brought an end to the barbaric practice of testing cosmetics by blinding live rabbits. He was a great friend of Singer's, and he was Singer's hero - in part because Spira demonstrated that the world is not simply divided into saints and sinners, and that some ethics are better than none. One of Singer's daughters told me that when Spira died she had never seen her father so upset.

Still, many of Singer's critics dismiss him as a secular puritan so inflamed by his idea of rectitude that he can't even recognise his own contradictions. Singer feels that this is unfair, and he may have a point: although he fails to live up to the rigid rules he has put down on paper, he probably comes as close to doing so as anyone could. He gives away 20 per cent of his annual income, including all royalties from Practical Ethics. He lives comfortably but frugally. He doesn't eat meat or fish, or wear leather. Yet Singer's writing is so high-handed that any inconsistency between his life and his work is hard to dismiss. Singer has certainly done nothing to impoverish himself, for instance, and his daughters also live comfortably, aided by the income of a trust set up by his father which - he would have to agree - none of them need.

Some opponents of utilitarianism say that when you turn human values into a series of preferences and run them all through a continuous personal calculator you risk dissolving the notion of human character completely. They call it moral economics. Others, who rely on rationality just as much as Singer does, would say that Singer's views are not as rational as he thinks they are. "He's always so damn logical," Bernard Williams told me. "But Singer leaves out an entire dimension of value. After all, who says his way is the right way to live? Every moral theory is based on somebody's intuition. He simply has the intuition that intuitions don't make sense. But how did he get there?" In Singer's eyes, though, philosophers like Williams rely too heavily on emotion to make good judgement possible. Singer feels that "intuitions" are vague, misleading, and unlikely ever to solve complicated problems. "Lay off with the `You reason, so you don't feel' stuff, please," he wrote recently in a short, quasi-fictional essay that was included in JM Coetzee's book The Lives of Animals. "I feel, but I also think about what I feel. When people say we should only feel... I am reminded of Goring, who said, "I think with my blood." See where it led him."

ANNE McDONALD lives in an airy Federal-style home in one of Melbourne's many suburban neighbourhoods. The building, which still has its turn-of-the-century pressed-zinc ceilings, is shrouded in vines and surrounded by cypresses. When I went to visit her there one crisp afternoon, it took her five minutes to answer the door. McDonald has athetoid cerebral palsy. She is bound to a wheelchair - literally strapped in with a seat belt - and she wears an alphabet board around her neck like a lobster bib. An elaborate computerised device sits in her lap, and this is what permitted her to say hello to me, in a recorded voice message that had been created from the several thousand utterances programmed into the machine. McDonald has long brown hair, and her eyes are an electric blue. They play an especially important role in her life, because she uses them to say yes and no: squeezed shut for yes, wide open for no.

She is exactly what Peter Singer had in mind when he wrote, in Practical Ethics, "It may still be objected that to replace either a foetus or a newborn infant is wrong because it suggests to disabled people living today that their lives are less worth living than the lives of people who are not disabled. Yet it is surely flying in the face of reality to deny that, on average, this is so." McDonald, who has known Singer for more than 15 years, agrees with much he has to say and is glad he has the nerve to say it. "There was a point when I should have been killed," she told me, referring to the years when she was treated as human refuse on the wards of Melbourne's St Nicholas Hospital. "I often prayed for it. But now I am alive," she said, tapping out her messages in phonetic code on her alphabet board, "and I enjoy my life very much."

McDonald is 38 years old. She was a breech baby, and that meant an abnormal amount of pressure was placed on the base of her brain as she passed through her mother's cervix. The result was a subdural haemorrhage, and she suffered massive - but very localised - brain damage. Athetosis makes her body quiver and quake. Spasmodically unable to command her muscles or vocal cords, she often sounds like a bird. But McDonald can think as clearly as any "normal" person.

Rosemary Crossley found McDonald in 1974, locked away in St Nicholas, where she had been since she was three. Crossley runs the Deal Communication Center, which provides services for people who can't talk as a result of conditions such as cerebral palsy, Down's syndrome, and strokes. In 1977, when McDonald was 16 years old and weighed 28lb, Crossley took her home for the weekend because she thought that the girl was about to die. That Sunday, Crossley and the man she lives with wanted to visit an art gallery, and they brought McDonald along in a baby stroller, which was the perfect size for her shrunken teenage body. "She started smiling at the paintings," Crossley told me. "She was looking at the Matisses, and she was transfixed by them. We could tell there was something there, and we decided to help her get it out." McDonald demonstrates as forcefully as anyone could that it is impossible to know what is going on inside the brain of a person who is unable to communicate. After a long struggle, McDonald learnt to read and write. She studied philosophy of science at Deakin University and fine art at the University of Melbourne, has published a book, travels around the world, and pays her taxes with at least as much pleasure as any citizen of Australia. In 1982, she and Crossley considered writing a book, Care, Cure, or Kill, about the fate of disabled infants. They eventually decided against it, but in the course of their research they went to interview Peter Singer.

It was the start of a strangely warm relationship. Singer's sister is a lawyer who has been active in supporting the disabled, and she and Singer have become the Deal Communication Center's biggest benefactors. Singer likes McDonald, and he would never say that she should die, while McDonald is clearly fond of Singer. Their principal conflict concerns how to determine what it is possible for a disabled person to achieve. "It is always a question of whether the future will be as bad as it looks," McDonald told me. If you know that it is going to be impossibly bleak and filled with suffering, she said, then Singer's view has more validity. But who, exactly, can know the future? "We can always be sure of one thing," McDonald said. "The dead have no regrets. Peter thinks that way. He knows me. But he doesn't think about individuals. We are all just a category to him." Advocacy groups for the disabled say that one reason Singer writes them off is that he places too much trust in the prognoses of doctors. The medical profession does tend to rate the quality of life for children with disabilities less highly than their parents do. But parents almost always follow medical advice on what to do about an infant with suspected or known disabilities. If the doctors say that the kindest thing would be to let the child die, most parents acquiesce. If, on the other hand, they say "Let's give the child a chance", that's what the parents will usually do.

Oddly, by arguing that disabled children should sometimes be killed, Singer seems, if anything, to be worrying too much about their pain. He is so devoted to the prevention of suffering that he dismisses the possibility that there might be more than that to many people's lives. "Most of us live through our own experiences," Rosemary Crossley told me. "So Peter assumes that people would be happy if they had the experiences that he had. For most of us, it is hard to live without reading, if you are a reader, or having sex, or jogging, or eating Chinese food. Whatever makes you happy, if you see people who cannot experience those things, you assume they cannot be happy. But that is not necessarily the case, and I don't think Peter has ever fully come to grips with that."

"Peter is a perfectly sincere man," McDonald told me. "But he thinks real life is not as important as intellectual life. So he can be very compelling when he talks about the intelligence and feelings of a pig. But he is somehow not as quick to understand what our problems and possibilities might be. He has all these big ideas, but he has never really got his hands dirty. Peter needs to get a little more involved in life if he wants to understand it."

THE PETER Singer who has just moved to America is not the unyielding radical who wrote Animal Liberation 25 years ago. In a sad fulfilment of Anne McDonald's wish, Singer has been dealt a bitter dose of real life. His mother, Cora, who was once an intellectually active and vibrant woman, has fallen ill with Alzheimer's disease. She no longer recognises Singer or his sister or any of her grandchildren. She is in a state that Helga Kuhse, who is her medical executor as well as her son's closest academic collaborator, described to me as one in which she would clearly not want to be alive any longer: "She always said, `When I can't tie my shoes and I can't read, I don't want to be here.' Those were her criteria, physical and mental. And she knew what she was saying - she was a doctor. We don't have active euthanasia in this country, but she certainly would not want drugs to treat an infection or anything else that could prolong her life."

Singer would never kill his mother, even if he thought it was what she wanted. He told me that he believes in Jack Kevorkian's attempts to help people die, but he also said that such a system works only when a patient is still able to express her wishes. Cora Singer never had that chance; like so many others, she slipped too quickly into the vague region between life and death. When Singer's mother became too ill to live alone, Singer and his sister hired a team of carers to look after her at home. Singer's mother has lost her ability to reason, to be a person, as he defines the term. So I asked him how a man who has written that we ought to do what is morally right without regard to proximity or family relationships could possibly spend tens of thousands of dollars a year on private care for his mother. He replied that it was "probably not the best use you could make of my money. That is true. But it does provide employment for a number of people who find something worthwhile in what they're doing."

This is a noble sentiment, but it hardly fits with Peter Singer's rules for an ethical life. He once told me that he has no respect for people who donate funds for research on cancer or heart disease in the hope that it might indirectly save them or members of their family from illness, since they could be using that money to save the lives of the poor. ("That is not charity," he said. "It's self-interest.") Singer has responded to his mother's illness the way most caring people would. The irony is that his humane actions clash so profoundly with the chords of his utilitarian ethic.

That doesn't surprise Bernard Williams. "You can't make these calculations and comparisons in real life. It's bluff," Williams told me. "One of the reasons his approach is so popular is that it reduces all moral puzzlement to a formula. You remove puzzlement and doubt and conflict of values, and it's in the scientific spirit. People seem to think it will all add up, but it never does, because humans never do."

Singer may be learning that. We were sitting in his living room one day, the traffic noisy on the street outside his window. Singer has spent his career trying to lay down rules for human behaviour which are divorced from emotion and intuition. His is a world that makes no provision for private carers to look after addled, dying old women. Yet he can't help himself. "I think this has made me see how the issues of someone with these kinds of problems are really very difficult," he said quietly. "Perhaps it is more difficult than I thought before, because it is different when it's your mother." 2