The present volume is about philosophy of medicine and integrates philosophy of medicine as a chapter of philosophy of science. It is neither about bioethics, nor about the history of medicine, but it is comprehensive and encompasses the whole field of medicine including psychiatry. It is grounded on a first-order standpoint, and it strives to stay close to clinical or community medicine: it bestows an epistemological bottom-up account. It is not a review of the literature, and it is not intended to frame the debates, or to analyse and compare the various and substantial number of viewpoints although some authors' account may form the basis of the book when they fit into the development of its philosophical view of medicine.