If you followed that link, you’ll see a story about a young girl with leukemia who is told of a legend whereby if a person folds a thousand paper cranes their wish will come true. According to the story of the girl, she originally was going to wish to be well, but when she got to the end she wished for world peace instead. She was buries with a wreath of a thousand paper cranes.
In all of my searching, though, I cannot find reference of the original legend itself, only mentions of people being told the legend.
I suppose the point, as my friend says, is that if you see it through, making the thousand cranes, during which you really can’t think of anything other than the wish you will make, by the end you’ll really know what your heart desires. In the girl’s case, being a victim of the atomic bomb herself, she (I assume) realized that she wanted less to get better herself and wanted more that the world would have peace and never see another atomic bomb drop.
I’ve been wondering what I would wish for if I decided to undertake the folding of a thousand cranes. I have no idea…
My friend has been keeping track of his progress on his blog.