Though most people apparently support the idea that we live in a complex society, a point of view that at least in principle inevitably leads to the conviction that complex evaluations and strategies are needed in order to effectively address the various problems presented by society itself, little attention is generally paid to the frequent presence of a low level of "complex thinking", which often characterizes violent people's beliefs and feelings. Instead, this perspective might be useful for many reasons, one of which being that moral judgements that often accompany educators' analysis of racist and violent beliefs and feelings could be enhanced by a more sophisticated critique where cognitive and emotional processes are examined per se and in all their structural relationships. In line with these considerations, our research aims to go beyond the study of the relationship between formal education and ethnic prejudice. More specifically, we intend to analyse the relationship between levels of presence of "complex thinking" and levels of acceptance of cultural diversity among youths in Italy. As an exemplar, we use some extracts from anonymous open-ended essays on issues related to multiculturalism recently written by some "racist" and some "non-racist" youths (aged 14-18). The essays are analysed through qualitative methods including textual analysis, discourse analysis, and content analysis, and, more specifically, through the use of some distinctive categories. A few of these categories have been elaborated in our previous research works (e.g., "concreteness" and "honesty"), while others (e.g., "unity and multiplicity" and "emotional granularity") are more strictly related to the specific constituents of "complex thinking". As a result, on the one hand, we will concretely see how some youths' low levels of "complex thinking" are often expressed in the construction of stereotyped and prejudiced representations of a multicultural social reality as well as in a frequently generic and simplistic description of their emotions. On the other hand, we will see how some youths' high levels of "complex thinking" are often expressed in the construction of a differentiated, integrated, and accurate representation of multiculturalism and in a precise, and refined description of their emotions, as a result of an autonomous and critical elaboration of their personal experiences and reflections. It goes without saying that this analysis necessarily recognizes the role that the socio-cultural context plays in affecting youths' cognitive and emotional processes characterising their attitudes toward cultural diversity. Our study should contribute to underlining the importance of fostering the development of high levels of complex thinking so as to strengthen youths' capability of building a more personal, autonomous, and complex outlook on their relationship with cultural diversity and with diversity in general.