Students often laugh at me, or hum, and smile when they see me, or two people look at what I say and then smile at each other.

How can I put it? You know there is a kind of magnet. Sometimes they attract each other and sometimes they repel each other. You can't see the power they produce, and so can people. Some people like you, some people hate you, and the result is also an energy between people, which we can't see, so don't care about other people's opinions, just do your duty and positive energy.