A professor gave a balloon to every student to write their name on it and throw in the hallway.The students were given 5 minutes to find their own balloon. No one found their balloon.
The professor told the students to take the 1st balloon they found and hand it to the person 1/2

whose name was written on it. Within 5 minutes, everyone had their own balloon.
The professor said to the students: "These balloons are like happiness. We will never find it if everyone is looking for their own. But if we care about other people's happiness, we'll find ours too."