In Better than Human?, noted bioethicist Allen Buchanan grapples with the ethical dilemmas of the medical revolution now upon us. Biomedical enhancements, he writes, can make us smarter, have better memories, be stronger, quicker, have more stamina, live much longer, be more resistant to disease and to the frailties of aging, and enjoy richer emotional lives. They can even improve our character, or at least strengthen our powers of self-control. In spite of the benefits that biomedical enhancements may bring, many people instinctively reject them. Some worry that we will lose something important-our appreciation for what we have or what makes human beings distinctively valuable. To think clearly about enhancement, Buchanan argues, we have to acknowledge that nature is a mixed bag and that our species has many design flaws. We should be open to the possibility of becoming better than human, while never underestimating the risk that our attempts to improve may backfire.