It was a very foggy day in London. Mr. Smith had arrived from Edinburgh to go to a very important meeting, but no buses or taxis were running because the drivers were not able to see more than a yard in front of them. It was nine o'clock, and his meeting was not till ten, so he thought that he would walk to the office where it was going to be. But when he looked out into the street, he saw that nobody was even trying to walk anywhere.
While he was standing there, saying unpleasant things about the fog, and thinking that he would have to telephone to the office and say that he was not able to come, a young man came up to him and said, 'Sir, if you want to go somewhere, I can guide you.'
Mr Smith was very surprised and said, 'How can you find the way when there is thick fog everywhere?'
'Do not worry, sir,' answered the young man. 'Trust me.'
So Mr Smith told the young man where he wanted to go, took his arm, and they started. They walked quite fast, turning corners and crossing roads in various places.
At last Mr Smith thought, 'Perhaps this man is mad, or a thief. Perhaps I shall finish up death in the river.'
But a minute later, the young man stopped and said, 'Here is the place, sir.' Mr Smith was surprised to find that he had really reached the office he had been looking for. He gave the young man a pound and then said, 'How did you find the way in the fog?'
'I am blind, sir,' answered the young man, 'but I know London well, and it is exactly the same for me in the fog.'