Despite seventy years of continued integration, membership of the European
Union is still highly differentiated. The asymmetry of economic development concerns several areas. The aim of this analysis was to identify frequent disproportions in performance, as well as differences in the perception of these countries. The method was a comparison of selected EU member states according to Rokkan's approach of binary entities and Wallerstein's center- periphery model. However, objectively verifiable facts within the conceptual mapping of reality tend to be distorted by the creation of a mental map, when we automatically consider the original EU-15 to be more advanced than EU-13.
The analysis carried out does not confirm this assumption.