 It is sometimes said that the role of functions in a teleological theory of content is to explain how error (misrepresentation) is possible, rather than to explain how content is determined (Millikan 2004, 63), but the two go hand in hand. To see this, it helps to start with the crude causal theory of content and to see how the problem of error arises for it. According to the crude causal theory, a mental representation R represents that an F is present if and only if Rs are always caused by an F’s being present. One problem with this simple proposal is its failure to provide for the possibility of misrepresentation, as Fodor (1987, 101–104) points out. To see the problem, consider a mundane case where Joan’s belief that there is a cat (which is usually caused by cats) is caused by a small fox. The crude causal theory does not permit this characterization of the situation because, if a small fox caused Joan’s belief, then belief states of this type cannot represent that a cat is present; instead, their content must be something like a cat or a small fox is present. In other words, as soon as the state of a small fox’s being present causes Joan’s belief, it is included in the truth-conditions of that (type of) belief and so, on this theory, there is no logical space for the possibility of error: all candidate errors are transformed into non-errors by their very occurrence. Note that the problem of making room for error can also be described as the problem of specifying the content of representations in such a way that error is possible. So explaining how content is determined and how the possibility of error are accommodated are not separate tasks.