Since the doctrine of papal infallibility has been mentioned a copule of times, it is worth summarising what I was taught about it in a Catholic school at the age of about eight at a time when we still had the Latin Mass:

It became official in 1870, which is pretty recent given the age of the organisation and was much more to do with political structure than teaching per se. There was a long argument beforehand about a particular matter and the question arose whether the role of the Pope was similar to a monarch or president (ie listening to advisors and then making the definitive statement independently of their advice) or more like a chairman of a board (the board as whole decides, and the chairman is more of a spokesman.) Whichever structure applies, the board and/or advisors must back the decision and should not continue to promote any of the alternative viewpoints. If you like, collective responsibility applies.


(Yes, that was the sort of thing that eight year olds were expected to understand in my school. I'm pretty sure I did!)