'You think I am mad, don't you?' No response. The old man smiled further, as if he was enjoying himself thoroughly. His wrinkled cheeks and forehead, showing his age, did not stop his eyes from shining, which were still young. He had the look of a an enthusiastic teacher, ready to share his knowledge willingly, while also willing to listen to others. Then he said, quite abruptly, 'How do you know that it is I who is mad, and not you?'