Starting the next day, he was much quieter. When he felt something warm on his face, he wouldn't ask what the sun was. When he heard something singing, he wouldn't ask what birds were.
Eventually, he heard enough from other people to understand what it meant to be blind. He learned that the sky wasn't black, it was blue. The world wasn't black either. It was filled with many colors.
He also realized that he was different from the other children. They had all been able to see the world from the moment they were born, whereas he....
He thought about what his parents had told him, that he would be able to see the world after he grew up. That was a lie. And yet, he didn't want to believe that it was a lie, and continued to tell himself that after he grew up, he would be able to see.
The reason he couldn't see... was that he hadn't grown up yet.