In 'I Must Be Talking to Myself', best-selling author Mark Patrick Hederman traces the history of dialogue in the Roman Catholic church since its introduction in the 1960s by Pope John XXIII and provides a philosophical analysis of the idea of dialogue. He also suggests that we have only begun to understand the implications of this reality in our religious lives; that it was the Holy Spirit who must have inserted the idea into an otherwise unlikely constituency; that Christianity in the twenty-first century - which is becoming a minority interest - had better take this notion of Dialogue fully on board if it is to survive and to accomplish the unity which was the unambiguous precept of its founder.