Chandragupta's Chief Minister Chanakya was a very wise and well-read man. Once an envoy came from China to discuss the philosophies of politics with him. The Chinese envoy had a royal lifestyle and was also arrogant. He requested Chanakya for an appointment and was told to go to his house at night.
At the correct time the Chinese man reached the hut of Chanakya. He saw Chanakya sitting and writing something under the light of a very small lamp (diya). He was surprised and wondered why the Chief Minister should use such a small lamp and thought himself as much better off in China.
Chanakya got up, respectfully welcomed him and offered a seat. Before talks could begin, Chanakya put the diya off and lighted another one. After the discussions were over, Chanakya put off the new diya and lighted the old one back again!
As the envoy was going out he could not contain himself from asking Chanakya why he did all this. Chanakya said "When you reached my house I was doing my personal work for which I use my diya. When I started talking to you, I put it off and used the government diya which I have put off as soon as our discussions are over. I am sometimes the 'Chief Minister' and sometimes an 'ordinary citizen' and I know the difference between the two."