Pity, disgust, fear, cure, and prevention—all are words that Americans have used to make sense of what today we call intellectual disability. Inventing the Feeble Mind explores the history of this disability in the United States from its several identifications over the past 200 years—idiocy, imbecility, feeblemindedness, mental defect, mental deficiency, mental retardation, and most recently intellectual disability. Using institutional records, private correspondence, personal memories, and rare photographs, James Trent argues that the economic vulnerability of intellectually disabled people (and often their families), more than the claims made for their intellectual and social limitations, has shaped meaning, services, and policies in United States history.