Emil Kraepelin, a German psychiatrist, wrote in 1913 that the causes of schizophrenia were “wrapped in impenetrable darkness.” He outlined the symptoms that still characterize the disorder, including delusions, hallucinations and disorganized thinking. Kraepelin used a different term—“dementia praecox”—that reflected his belief in the disease's unremitting downward course (dementia) and its early onset (praecox).