Abstract

This paper discusses a new paradox, the paradox of infallibility. Let us define infallibility in the following way: (Def I) t is infallible if and only if (iff) everything t believes is true, where t is any term. (Def I) entails the following proposition: (I) It is necessary that for every individual x, x is infallible iff every proposition x believes is true. However, (I) seems to be inconsistent with the following proposition (P): It is possible that there is some individual who believes exactly one proposition, namely that she is not infallible. So, it seems to be the case that either (I) or (P) must be false. Yet, (I) is simply a consequence of (Def I) and (P) clearly seems to be true. This is the puzzle. I discuss five possible solutions to the problem and mention some arguments for and against these solutions.