Gregorio, The Hand Trembler is a book written by Alexander Hamilton Leighton that explores the life and personality of a Navajo Indian named Gregorio. The book is a psychobiological personality study that delves into the cultural and psychological factors that shaped Gregorio's life and personality.Gregorio was a well-known hand trembler, a traditional Navajo healer who uses his hands to diagnose and treat illnesses. Leighton examines the role of...