The doctrine of the sanctity of human life is in deep trouble, claims Australian philospher Singer (The Expanding Circle: Ethics and Sociobiology, 1981, etc.), who gives his own clear ideas of what should replace it in this decidedly provocative work. With crisp, dramatic tales involving brain-dead bodies, anencephalic infants, people in persistent vegetative states or with agonizing terminal illnesses, and other now-familiar hospital scenarios, Singer asserts that modern medical practice has become incompatible with a belief in the equal value of all human life. He argues that the ethical problems such situations pose would be simplified if we would only abandon our outdated thinking about life and death. He presents five commandments of what he calls the old ethic and suggests how they might be rewritten. In his scheme, the first, "Treat all human life as of equal worth," becomes "Recognize that the worth of human life varies"; the second, "Never intentionally take innocent human life," becomes "Take responsibility for the consequences of your actions." The third and fourth express Singer's views that people have the right to end their own lives and that unwanted children should not be brought into the world. All of these will trigger outrage in various quarters, but perhaps most provocative is his fifth revision: "Treat all human life as always more precious than any nonhuman life" becomes "Do not discriminate on the basis of species." A founder of the Animal Rights Movement, Singer argues that the right to life properly belongs not to Homo sapiens but to persons, by which he means those beings that possess self-awareness. In this view, an embryo or someone in an irreversible coma is clearly not a person, but a gorilla or a baboon is. Singer can't quite figure out how to regard newborn humans, but he gives infanticide a serious look before backing off. By going to the very core of our beliefs about life, Singer has created just about as controversial a book as possible.