His sharpest criticism is directed against the principle of assimilation, with its implication that outsiders settling in Germany should abandon their own cultural identity. In the story "Als der Meister auftrat" ("When the Master Entered") in Das Letzte Wort der Wanderratte, the migrant worker Hassan has himself transformed into a Siegfried, only to discover that the deception is untenable. The magician who sells him his German skin is named Gnussapna – an inversion of Anpassung, assimilation.