Scientific achievements have significantly changed the world. However, science is sometimes wrong—sometimes even catastrophically wrong. Understanding the validity of scientific conclusions and assessing the degree to which they can be trusted have important implications for personal choice, public debate, and the development of public policies and laws. What are “scientific facts” based on? How much can we trust them? What is science and what is not? In this book, the author seeks a working definition of science and its properties from the point of view of a practicing scientist, bringing together the achievements of philosophy, psychology, history, sociology and anthropology into a holistic system.