There is a statue which was not made by a human being, which stands in the heart of a certain city. It is 500 feet (~166 m) high and can be seen from miles away.
A young boy saw that statue and saw the life in it. He wanted to go see it, and his parents took him once. He looked up at it from its feet and it didn't look quite the same to him. But he believed in it, and touched the statue's feet, polished by the touch of other citizens.
From then on, he knew that the statue was for him, and he went about his normal days as a young boy, not thinking too much of it.
He read the newspaper when he had nothing to do after school, and saw that there were blind people who had trouble finding the statue. People tried to give them very good directions, but it turns out that it's hard to give directions to blind people if you're sighted.
This weighed on him. He decided that he needed to learn how to make better directions for blind people to find the statue.
He forgot about this in the short run, but remembered it with his whole life. He found that while a sighted person only needed to be shown the statue from a distance, and told "just find a way to get through the streets -- you'll make it", a blind person had to be told to go from this street to that street -- the city has a lot of canyons cutting streets into pieces, so there's no one or two streets that can get you to the statue. And unfortunately, in this city there are blind people who can't even process the idea of a street and must be told precisely how many steps to take in which direction, orienting themselves to the sounds and smells along the way.
So he knew that what he must do was to become blind himself, and even damage his ability to process streets, in order to enter into the reality of the blind people he wanted to guide to the statue. So he let his eyesight dim, from reading old street maps, and learned to read Braille.
And he worked diligently, as a guide for the blind, proving from Braille maps exactly where the statue ought to be.
He had always been content, as when a boy, to let the statue be off in the distance, but one day he wished to see the statue, to believe in it. So he looked up the route to get from right where he was to the statue, and carefully followed it, avoided getting hit by a car, avoided tripping on the cracks in the pavement.
And he arrived at where the statue ought to be, but he could not see it. Eventually someone led him to the foot of it, and he touched the foot. He could only believe that the rest of the statue was there.