Icon Indice Symbol

"Peirce thought that “representations” generate further interpretants in one of three possible ways. First, via “a mere community in some quality” (W2 .56). These he calls likenesses, but they are more familiarly known as icons. Second, those “whose relation to their objects consists in a correspondence in fact” (W2 .56) are termed indices. And finally, those “whose relation to their objects is an imputed character” (W2. 56) are called symbols. Put simply, if we come to interpret a sign as standing for its object in virtue of some shared quality, then the sign is an icon. Peirce's early examples of icons are portraits and noted similarities between the letters p and b (W2. 53–4). If on the other hand, our interpretation comes in virtue of some brute, existential fact, causal connections say, then the sign is an index. Early examples include the weathercock, and the relationship between the murderer and his victim (W2. 53–4). And finally, if we generate an interpretant in virtue of some observed general or conventional connection between sign and object, then the sign is a symbol. Early examples include the words “homme” and “man” sharing a reference. (W2. 53–4)." - Peirce's Theory of Signs