Mental disabilities in western civilization from ancient rome to the prerogativa regis y. Intellectual disabilities = mental defect, mental deficiency, mental retardation, developmental disability, mental handicap, and mental subnormality. y neugebauer & stainton described the distinction between mental retardation and mental illness in the prerogativa regis (document from 13th century). Greece and the 13th century in england, a concept of intellectual disability separated from a generic impression of mental illness. Words and sources y mental illness and cognitive deficits were confused in the earlier periodprobably due to a lack of clear conceptual distinction, but may also be due to confusion of concepts by the earlier translators. The mishnah y a document bringing together, interpreting, and making more explicit jewish law. It y focused on a) various forms of religious observance, b) the ability to value the economic worth of another person, and c) the degree of responsibility for certain acts in everyday life.