Goodman is interested in the 'routes' of reference—how symbols denote, exemplify, or refer in complex and indirect ways.

Hence, Goodman appears to analyze pictorial representation as an ambiguous concept, ambiguous, that is, between a denotational sense (“is a picture of a so-and-so”) and a non-denotational sense (“is a so-and-so-picture”). This may be seen as a disadvantage vis-à-vis “perceptual” theories of depiction such as those proposed, for instance, by Richard Wollheim (1987) and Kendall Walton (1990) (cf. Robinson 2000). Yet concerns on Goodman’s treating the concept of depiction as ambiguous are misplaced