 Suppose, for the sake of argument, we grant that intuitions properly understood and had under ideal conditions by people with a deep understanding of the relevant concepts can justify certain propositions. But can they yield knowledge about the external world? Carrie Jenkins has argued that they can insofar as the concepts that play a role in a priori justification have been shaped by experience. She thinks that for knowledge (not justification) our concepts must be grounded. By this she means that they must accurately and non-accidentally represent the world. So the concept table can be grounded for a person in a world where there are tables but not for a brain-in-a-vat (BIV) (Jenkins 2008a: 128–29). For a concept to be justified for Jenkins is for it to be “respectable” for us to rely on it (by which, I believe, she means that we would be epistemically blameless in relying on it) as “a relevantly accurate guide to the world” (Jenkins 2008a: 129). So a BIV can have a justified, though not a grounded concept, about things existing in the external world.