There was a boy who had a very bad character. One day, his father gave him a bag of nails and told him that every time he lost his cool, drive a nail into the fence in the backyard of the house. On the first day, the boy drove 37 nails. The next day, less, and so on the rest of the days. The little boy was realizing that it was easier to control his temper and bad temper than having to drive the nails into the fence.

Finally the day came when the boy did not lose his cool even once and was joyful to tell his father. He had finally managed to control his bad temper! His father, very happy and satisfied, then suggested that for every day he controlled his temper, he pull a nail out of the fence. The days passed and when the boy finished removing all the nails he went to tell his father.