 Yet incompatibilists reply that (ironically) these very reflections reveal apriori something that should not be apriori (Brown 1995, Boghossian 1997). Namely: If Oscar is aware that he has no such hypotheses (i.e., if he is “agnostic” about chemical essences), then (1) must be knowable apriori. In more detail, if Oscar is agnostic about chemistry and knows that apriori about himself, he can use the reflections above to know apriori that his water thoughts metaphysically require the existence of water or a community. From there, apriori knowledge of E seems imminent.