A pathologist is a doctor — sometimes a scientist working with doctors — whose work is to study disease by looking very closely at the body. They examine blood, tissue, or, in some cases, a body after death, to find out what went wrong and why. Other doctors then use that answer to treat a living patient, or a court uses it to understand a death. Films love the second picture, so students often think a pathologist only works with the dead. Though actually, many spend their days on small samples from people who are still alive: Is this lump cancer? What is this infection? They usually do not sit and chat with patients the way a family doctor does; they work in a lab. The name of the field is pathology. The pathologist is the person who does that work.