Eugen Bleuler (1857 -1939) was a Swiss eugenicist and psychiatrist who studied progressive and physically-based mental illnesses and in fact coined the now commonly used terms "schizophrenia," "schizoid," "autism," "depth psychology" and "ambivalence." A contemporary and colleague of both Sigmund Freud and Carl Jung, he pioneered the idea that some mental illnesses were the result of physical deterioration of the brain. His research effectively replaced the term "dementia praecox" with the more modern "schizophrenia." He also contended that organically-based mental illnesses were not curable but could be managed. His works, not translated into English before the 1950's contended that persons suffering from these organic mental illnesses should be sterilized and thus be unable to reproduce thereby eliminating the faulty genetics from the human gene pool.