 The skeptical scenarios (dreaming, brains in vats, differently situated sense organs, etc.) call our attention to a crucial distinction between appearance and reality: how things perceptually appear is not necessarily how things really are; things could appear the same though really be different, and they could appear to be some other, incompatible way and really be the same. Further reflection on the scenarios suggests that although I might know very little—perhaps nothing—about how things are in the external world, I can nevertheless know quite a lot about how it appears to me that things are. This engenders a shift from thinking about perceptual appearances as features of objects (e.g., “the appearance of the house was quite shabby”), to thinking of them as mental states—experiences—of the perceiving subject (e.g., “she had a visual appearance/experience as of a house”). Finally, it seems that if we are to know anything about the external world at all, that knowledge must be indirect, for what is directly before me is not the world itself, but only these perceptual appearances. I know and have justified beliefs about the external world only insofar as I know and have justified beliefs about appearances.