A philosopher, a barber and a bald person were travelling together. They lost their way, and as night fell, they thought it would be better to sleep in the open air instead of wandering about at night. For safety, it was decided that they would keep watch by turns.
The first lot fell on the barber. As the other two slept, he felt more and more sleepy and bored. To keep awake, he shaved the head of the philosopher to pass the time. Next was the turn of the philosopher, and at the end of his time, the barber woke him up.
The philosopher raised his hand to scratch his head, and exclaimed "You have made a mistake friend , you woke up the bald person instead of me"