There were three men walking up a steep hill, each very tired, with a heavy burden on his back. Then there stepped up to them a strong kind man, who said to them, "Let me take your burdens; I will carry them for you." But the first man said, "I have no burden," for he had carried his burden so long that it seemed like his clothes, or like part of his body, so that he did not feel it, and did not know how much better he could walk without it. So the first man would not have his burden touched.
The second man was very selfish and unkind himself, and he thought that all other people must be selfish and unkind, so he said, "You want to play me some trick; I do not believe you want to carry my burden; I will not let you touch it."
The third man was very tired indeed, and was saying to himself, "Oh, who can help me? for I feel that I cannot carry this terrible weight any further;" and when he felt the stranger touch him on the shoulder, and offer to take his burden, he said at once, "It is very kind of you; I am very thankful; please take it, for I see you can bear it and I cannot."
Edwin Abbott Abbott, Parables for Children. Abbott is most famous for being the author of Flatland.