Advanced knowledge and science are universal languages, requiring almost no translation, thus spreading easily. Cultural differences in taste need not prevent cooperation on standards for peaceful coexistence, mutual recognition, and tolerance. In Europe, progressive ideas supporting this cooperation emerged over time: cosmopolitanism began in ancient Greece (the term appears in the 4th century BCE with Diogenes of Sinope, who called himself a “citizen of the world”) and resurfaced in the Enlightenment, emphasizing universal rights and global citizenship. The “Republic of Letters” of the 17th–18th centuries further advanced these ideals through cross-border exchanges among scholars, writers, and philosophers.