Derived from the Greek ‘eikōn’, meaning ‘resemblance’ or ‘image’, it is generally used to refer to sacred images of Christian saints and other religiously significant figures. American metafiction Peirce, Charles Sanders adopted this term as one of three classifications of types of sign (the other two being the index (semiotic) and the symbol). For Peirce, the icon is an example of what he called firstness because it is able to signify by virtue of its own qualities (i.e. without reference to an object or convention). A pure icon in Peirce’s sense is an image of a thing so closely resembling the thing it represents that we forget we are looking at an image. It is, in this sense, a theoretical possibility, not an actuality.