This article contains a translation from Latin of an 1815 medical dissertation presented to the University of Edinburgh. The subject is hysteria; the author was John-Baptiste Philip, a mixed-race (‘coloured’) Trinidadian. Philip’s family was French Grenadian in origin. His father relocated to Trinidad in the late Spanish colonial period and Philip himself came of age in the early English colonial period. A well-to-do landowner and slaveholder, the elder Philip sent his sons to London and Edinburgh for education. The existence of this 1815 dissertation has long been known to Caribbeanists, but possibly because of alternate spellings of the author’s name no one has identified it, much less read it in Latin. The work is remarkable, especially when read alongside Philip’s 1823 petition to Earl Bathurst, Secretary of State for War and the Colonies. In his works, Philip inaugurated one of the important themes of Caribbean literature and philosophy, which is that racially motivated mistreatment and inequality drive people into extreme mental and emotional states often thought of as madness. Another element of his works, widely echoed well into the twentieth century, is that men’s hysteria is cured by their gaining political rights while women’s is alleviated by their being secured in domestic life.