 In general, if a philosopher A claims that the argument of philosopher B does not go through, it is a point in favor of his view if he can provide an error theory, that is if he can explain why the argument may appear correct in the first place. The New Knowledge/Old Fact View can claim to have an error theory with respect to the knowledge argument. Given the cognitive independence of physical and phenomenal concepts of blueness it appears as if we could imagine a situation where everything Mary knew before release were fulfilled but not what she came to know after release (and this can be taken to imply that she does come to know new facts). But, according to the New Knowledge/Old Fact View this is an illusion. There is no such possible situation. What Mary learns after release is made true by a physical fact that she already knew before her release. Some versions of the New Knowledge/Old Fact-View will be briefly described in what follows.