In "Toward the Final Solution", he claimed that racial stereotypes were rooted in the European tendency to classify human beings according to their closeness or distance from Greek ideals of beauty. "Nationalism and Sexuality: Middle-Class Morality and Sexual Norms in Modern Europe" extended these insight to encompass other excluded or persecuted groups: Jews, homosexuals, Romani people, and the mentally ill. Many 19th-century thinkers relied upon binary stereotypes that categorized human beings either as "healthy" or "degenerate", "normal" or "abnormal", "insiders" or "outsiders". In "The Image of Man: The Creation of Modern Masculinity", Mosse argued that middle-class male respectability evoked "counter-type" images of men whose weakness, nervousness, and effeminacy threatened to undermine an ideal of manhood.