Given content externalism, then, Warfield cannot have the desired a priori knowledge of premise 1 (“I think that water is wet”). Does this mean that his use of premise 1 begs the question? Apparently so. Certainly, from a Putnamian point of view, the question is begged. For on that point of view, one could not have warrant for premise 1 unless one had warrant to believe that (unlike a BIV) one had satisfied the causal constraints on having the concept water. Thus it would seem that—absent any a