When a journalist meets a physicist in front of a blackboard, mathematics becomes a game. Seven curious and entertaining dialogues, born from real conversations between Sara – passionate but not an expert – and Massimiliano Sassoli de Bianchi, quantum physicist and populariser. Between divisibility criteria, infinite scales, mysterious numbers and optical illusions, each chapter is an invitation to rediscover the wonder of mathematical thinking. A book for those who loved (or hated) mathematics, and for those who are ready to rediscover it with new eyes.