Definition of infallible

The word "infallible" originated in Latin, where it was "infallibilis." In medieval theology and philosophy, it was used to describe something that could not be fallen into error or mistake. In the context of religion, the term was first used to describe the interpretation of sacred texts and doctrines as interpreted by church authorities. In the Catholic Church, the concept of papal infallibility - the belief that the Pope is free from the possibility of error when speaking ex cathedra (with authority) on matters of faith and morality - was defined in 1870 by the First Vatican Council. This teaching affirmed the Pope's role as the spiritual leader of the Catholic Church and the final arbiter of orthodoxy. Outside of religious contexts, the term "infallible" is used to describe things or processes that are free from error or mistake. This may include things like scientific laws, mathematical formulas, or technical standards. However, in these cases, it's important to note that the term "infallible" is often used hyperbolically and should be interpreted cautiously, as no human endeavor is completely free from the possibility of error or mistake.