The first part of the dissertation analyses iconicity as a special form of semiotic object categorisation on the basis of a four part, structurally inspired sign model  (group µ, L. Prieto). The central concept to this is the abstract relevance (K. Bühler) which connects the two dichotomies of expression and content as well as the variant and invariant. In this way talk of the "common properties" of iconic sign carrier and the presented can be made more precise. 

The second part, which develops the pragmatic relevance theory (Sperber/Wilson) differenciates between two areas of pragmatics of iconic sign. The first analyses the dependence of iconic categorisation on contextual factors. The second area, however, examines the further meaning effects which this act of categorisation creates in its respective context. These are not specifically iconic, but can be explained using general pragmatic rules which are also at the basis of all other forms of implicit communication. 

The combination of a structuralist and a  pragmatic approach shows that both these semiotic thought-processes are not only compatible but also supplement one another usefully.