The text to be classified is compared with the contents of a relevance lexicon in which the significant words of the texts to be classified per text class and their relevance to the text classes is stored. The fuzzy set is calculated which specifies for the significant words of the text to be classified, their occurrence per text class and their relevance to the text class. A probability calculation is used for determining the probability with which the fuzzy set occurs per class for the corresponding class. The class having the highest probability is selected and the text is allocated to this class.