Transplant surgeon pioneer Thomas Starzl. Last June he supervised the surgical team that transplanted a baboon's liver into a 35 year-old man who was dying of hepatitis B. It has since become known that the patient was HIV-positive, though he showed no symptoms of the disease. The case raised questions about whether it's ethical to "experiment" on a person who is HIV-positve. Starzl has a new book, called "The Puzzle People."