The great artists, it is said, see the world with the eyes of children. The great scientists retain their childlike curiosity. And the great athletes? They compete as they did in the school yard. A pattern is emerging, as if the price we pay for joining the adult world, with its responsiblities and repressions, its complicated, compromised pleasures, is too high. Alejandro Valverde, 41 and the oldest competitor at the 2021 Giro di Sicilia, rode yesterday’s stage with the magical lack of inhibition that distinguishes him.