Abstract
This article provides a historical, philosophical, and psychological analysis of the recent discovery that reoviruses are oncolytic, capable of infecting and destroying many kinds of cancer cells. After describing Patrick Lee's very indirect path to this discovery, I discuss the implications of this case for understanding the nature of scientific discovery, including the economy of research, anomaly recognition, hypothesis formation, and the role of emotion in scientific thinking. Lee's discoveries involved a combination of serendipity, abductive and deductive inference, and emotional cognition.