Skepticism and Contextualism

Has Tom spoken truly? Surely, Jones’s epistemic position seems good enough for satisfying the predicate ‘knows that the animals in the pen are zebras’ (henceforth ‘knows Z’): Jones has visual experiences of a black and white striped horse-like animal, she can discriminate reliably between zebras and antelopes, she has read the sign on the pen that reads ‘Zebra Pen’, etc. Thus, Tom’s utterance of (1) seems to be a paradigm case of a true ‘knowledge’ attribution. Next, imagine a couple, Bill and Kate, walking along. Bill, a would-be postmodernist artist, gives details of his latest ideas: he envisions himself painting mules with white stripes to look like zebras, putting them in the zebra pen of a zoo and thereby fooling visitors. Our couple randomly considers Jones, and Kate claims, at the same time as Tom is asserting (1):