This spring, the President's Council on Bioethics released a 555-page report, titled Human Dignity and Bioethics. The Council, created in 2001 by George W. Bush, is a panel of scholars charged with advising the president and exploring policy issues related to the ethics of biomedical innovation, including drugs that would enhance cognition, genetic manipulation of animals or humans, therapies that could extend the lifespan, and embryonic stem cells and so-called "therapeutic cloning" that could furnish replacements for diseased tissue and organs. Advances like these, if translated into freely undertaken treatments, could make millions of people better off and no one worse off. So what's not to like? The advances do not raise the traditional concerns of bioethics, which focuses on potential harm and coercion of patients or research subjects. What, then, are the ethical concerns that call for a presidential council?

Many people are vaguely disquieted by developments (real or imagined) that could alter minds and bodies in novel ways. Romantics and Greens tend to idealize the natural and demonize technology. Traditionalists and conservatives by temperament distrust radical change. Egalitarians worry about an arms race in enhancement techniques. And anyone is likely to have a "yuck" response when contemplating unprecedented manipulations of our biology. The President's Council has become a forum for the airing of this disquiet, and the concept of "dignity" a rubric for expounding on it. This collection of essays is the culmination of a long effort by the Council to place dignity at the center of bioethics. The general feeling is that, even if a new technology would improve life and health and decrease suffering and waste, it might have to be rejected, or even outlawed, if it affronted human dignity.

Whatever that is. The problem is that "dignity" is a squishy, subjective notion, hardly up to the heavyweight moral demands assigned to it. The bioethicist Ruth Macklin, who had been fed up with loose talk about dignity intended to squelch research and therapy, threw down the gauntlet in a 2003 editorial, "Dignity Is a Useless Concept." Macklin argued that bioethics has done just fine with the principle of personal autonomy--the idea that, because all humans have the same minimum capacity to suffer, prosper, reason, and choose, no human has the right to impinge on the life, body, or freedom of another. This is why informed consent serves as the bedrock of ethical research and practice, and it clearly rules out the kinds of abuses that led to the birth of bioethics in the first place, such as Mengele's sadistic pseudoexperiments in Nazi Germany and the withholding of treatment to indigent black patients in the infamous Tuskegee syphilis study. Once you recognize the principle of autonomy, Macklin argued, "dignity" adds nothing.