Empathy is a thing constantly asked for and stressed as a central skill and character trait of the good physician and nurse. To be a good doctor or a good nurse one needs to be empathic-one needs to be able to feel and understand the needs and wishes of patients in order to help them in the best possible way, in a medical, as well as in an ethical sense. The problem with most studies of empathy in medicine is that empathy is poorly defined and tends to overlap with other related things, such as emotional contagion, sympathy, or a caring personality in general. It is far from clear how empathy fits into the general picture of medical ethics and the framework of norms that are most often stressed there, such as respect for autonomy and beneficience. How are we to look upon the role and importance of empathy in medical ethics? Is empathy an affective and/or cognitive phenomenon only, or does it carry moral significance in itself as a skill and/or virtue? How does empathy attain moral importance for medicine? In this paper I will attempt to show that a comparison with the Aristotelian concept of phronesis makes it easier to see what empathy is and how it fits into the general picture of medical ethics. I will argue that empathy is a basic condition and source of moral knowledge by being the feeling component of phronesis, and, by the same power, it is also a motivation for acting in a good way.