The Greek noun hedra from Homer, kathedra from Thucydides, designates a chair or seat. In the Roman architectural form-the basilica, built with or without permanent seats, exedras, and used for the operation of government or court-a moveable chair could be brought in for the presiding officer. The chair, like the more specialized “throne,” came to represent the authority of the office. In the church secular it is the seat of the bishop, in the church regular that of the abbot, who are understood when seated to preside; the cathedral is simply the place of the chair. The notion ex cathedra, “out of the chair,” conveys the voice of authority or its codified or written pronouncements. In the Roman Catholic Church at Vatican Council I the status of the bishop of Rome was confirmed in that, when speaking as the successor of Peter, his words concerning faith and morals had the infallible character of apostolic doctrine.