The Chinese Rites Controversy is the clearest historical instance of the question and it had consequences. Jesuit missionaries in China, following Matteo Ricci, argued from the late sixteenth century that the ancestral rites and the honours paid to Confucius were civil and social observances rather than idolatry, and could therefore be retained by Chinese Christians; Dominicans and Franciscans disagreed. Rome ruled against the Jesuits in 1704 and definitively in the bull Ex quo singulari in 1742. The Kangxi emperor, who had been sympathetic, responded by restricting and then expelling missionaries who would not accept his position, and Christian missions in China were substantially curtailed for the following century. The Vatican reversed the prohibition in 1939, permitting Catholics to participate in ancestral ceremonies understood as civil honours. The underlying question — whether Confucianism is a religion, a philosophy, an ethical system or simply the operating assumptions of a civilisation — remains open, is answered differently in Chinese, Korean and Western scholarship, and has always carried political weight, including for whether it may be taught in a state school.