Visual Icons

ABSTRACT

Philosophers often characterize perception as image‐like. There is little agreement, however, about what constitutes an imagistic or iconic representation. This article identifies five signature properties of iconic representations endorsed in the philosophical and scientific literature: item‐richness, feature‐richness, spatiotemporal composition, holistic composition, and analog primitives. The article identifies a candidate class of visual processes— scene‐based early vision —and argues that the signature properties of icons cluster together in those processes. It then uses this ostension of a natural kind in visual perception to sketch a deeper theory of icons, outlining a hierarchy of more and less restricted forms of iconicity. Iconic representations are compositional structures built by coordinating analog dimensions in a multidimensional space. Visual icons are, like photographs and realist paintings, a more restricted case: They involve coordination of optional, repeatable dependent dimensions with mandatory, non‐repeatable independent dimensions. Coordinating dependent and independent dimensions, with some additional constraints, allows visual icons to index repeatable feature‐instances in computationally useful ways and provides a deeper understanding of why icons exhibit their characteristic properties.