Chaves is the Brazilian title for El Chavo del Ocho, the Mexican comedy series created by Roberto Gómez Bolaños that became a lasting hit in Brazil through its Portuguese dub. The phrase “Eu não sei, mestre” comes from its schoolroom scenes, where Chaves often answers his teacher with childlike honesty. Clips from the show circulate widely on Brazilian social media and messaging apps, where short lines are reused as reactions, and this one survives because it is instantly recognisable, easy to understand and perfect for moments of playful ignorance.