A false leaf

O. Henry in his novel "the last leaf"

in a story, said: A patient lying in bed, desperately looking out a sweep of the storm by autumn trees. He suddenly discovered that, in that tree, even has a light green leaves did not fall. Patients want, such as the leaf fall, and my life is over. So he spends his time looking at the piece of leaf, wait for it to fall, it quietly waiting for the end of his life. But that has hardly ever leaves, even until the patient's body fully restored to health, it still leaves Pitt as jade.
In fact, that the trees do not leaf, leaves a painter painted, and it is not true leaves, but leaves it to the true vivid real effect, given that patient a strong belief:.

alive, as long as the piece of leaf do not fall, my life will not die. The results, he really recovered, out of the room to see what happens under the tree.
He stood under the tree, being moved by the artist's intentions.
Because the artist is the only person to understand his secret heart, artist knew that he was waiting for after all the leaves fall and then quietly end their own lives. Thus, the painter was designed along the patient's mind so a fake leaf. Is this piece of fake leaves, to give him the courage to continue to live into.
Is not really a viable piece of leaf, but the person's beliefs