A creative scholar, translator and intellectual. John was E. G. Browne Lecturer in Persian Studies at Cambridge. He pioneered work in the study of Shi'i usul al-fiqh using modern semiotics. He taught English in Casablanca, Morocco. There he perfected his French, picked up some Berber and had his first contact with Islam. John having embraced Islam and took his name Yahya sought to bring mutual understanding between the 'West' and Islam. Yahya Cooper died in Rheims, France.