 One way to resist McKinsey’s incompatibilist conclusion that the privileged access thesis and externalism about mental content cannot be true together is to argue that Water is non-transmissive. Since knowledge is presumably closed under known entailment, it remains true that s cannot know P9 and P10 while failing to know Q9. However, McKinsey paradox originates from the stronger conclusion—motivated by the claim that Water is a deductively valid argument featuring premises knowable non-empirically—that s, by running Water, could come to know non-empirically the empirical proposition Q9 that she or members of her community have had contact with water. This is precisely what could not happen if Water is non-transmissive: in this case s could not learn Q9 on the basis of her non-empirical justification for P9 and P10, and her knowledge of the entailment between P9, P10 and Q9 (see mainly Wright 2000, 2003 and 2011, and Davies 1998, 2000, 2003a, 2003b and 2009).