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Papal Infallibility

Melvyn Bragg and guests discuss the history of the idea that Popes cannot err when defining a doctrine, in office, proclaimed at the First Vatican Council 1869-70

Melvyn Bragg and guests discuss why, in 1870, the Vatican Council issued the decree ‘pastor aeternus’ which, among other areas, affirmed papal infallibility. It meant effectively that the Pope could not err in his teachings, an assertion with its roots in the early Church when the bishop of Rome advanced to being the first among equals, then overall head of the Christian Church in the West. The idea that the Pope could not err had been a double-edged sword from the Middle Ages, though; while it apparently conveyed great power, it also meant a Pope was constrained by whatever a predecessor had said. If a later Pope were to contradict an earlier Pope, then one of them must be wrong, and how could that be…if both were infallible?


Tom O’Loughlin
Professor of Historical Theology at the University of Nottingham

Rebecca Rist
Professor in Medieval History at the University of Reading


Miles Pattenden
Departmental Lecturer in Early Modern History at the University of Oxford

Producer: Simon Tillotson and Julia Johnson

Available now

52 minutes

Last on

Thu 10 Jan 2019 21:30


Tom O'Loughlin at the University of Nottingham

Rebecca Rist at the University of Reading

Miles Pattenden at the University of Oxford

Papal infallibility - Wikipedia



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Walter Ullmann, Law and Politics in the Middle Ages: An Introduction to the Sources of Medieval Political Ideas (Cornell University Press, 1973)

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Walter Ullmann, A Short History of the Papacy in the Middle Ages (Routledge, 2002)



  • Thu 10 Jan 2019 09:00
  • Thu 10 Jan 2019 21:30

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