There was a young monk in China who was a very serious practitioner of the Dharma.
Once, this monk came across something he did not understand, so he went to ask the master. When the master heard the question, he kept laughing. The master then stood up and walked away, still laughing.
The young monk was very disturbed by the master's reaction. For the next 3 days, he could not eat, sleep nor think properly. At the end of 3 days, he went back to the master and told the master how disturbed he had felt.
When the master heard this, he said, "Monk, do you know what your problem is? Your problem is that YOU ARE WORSE THAN A CLOWN!"
The monk was shocked to hear that, "Venerable Sir, how can you say such a thing?! How can I be worse than a clown?"
The master explained, "A clown enjoys seeing people laugh. You? You feel disturbed because another person laughed. Tell me, are you not worse than a clown?"
When the monk heard this, he began to laugh. He was enlightened.