Modern medicine is built on a long history of medical experimentation. Experiments in the past often exploited more vulnerable patients. Questionable ethics litter the history of medicine. Without such experiments, however, millions of lives would be forfeited. This paper asks whether all the ``unethical'' experiments of the past were unjustifiable, and do we still exploit the poorer members of the community today? It concludes by wondering if Harris is right in his advocacy of a moral duty to participate in medical (...) research. (shrink)