Why has science so dramatically altered how we live and how we think about ourselves? What is the greatest scientific idea of all time? According to Professor Steven L. Goldman, one is tempted to speak of scientific discoveries as the source of science's power to be a driver of social change—that scientists have been discovering new truths about nature, and that the change follows from that. But I argue that it is scientific ideas that are responsible for this change. Ideas are the source of science's power—not discoveries."