In his seminal text “Logic as Semiotic: The Theory of Signs,” C.S. Peirce defines an index as a category of sign that maintains a physical tie to its referent. To elucidate this characterization, Peirce gives a number of examples, including the following: “Photographs, especially instantaneous photographs, are very instructive because we know that they are in certain respects exactly like the objects that they represent.”1 This parenthetical reference to photography would later be seized upon… [read more »]