"In 1909, Sigmund Freud told the that "the position of hypochondria is still suspended in darkness," and more than a hundred years later it does not feel as if there is much light on the subject. Even in the most widely used and up-to-date clinical literature, its definition is still shifting and changing. For instance, for the latest edition of the ' ('), which was published in 2013 by the and is often referred to as "the bible of psychiatry," the diagnosis of hypochondria was entirely recategorized into two separate entities: and illness anxiety disorder. Both describe patients with "extensive worries about health," but the former features so-called somatic or physical symptoms the patient feels in their body that medicine cannot detect or explain, whereas the latter is focused solely on "preoccupation with having or acquiring a serious illness" and "excessive health-related behaviors.""