One day, the peace-loving inhabitants of Earth asked an extremely powerful wizard to stop all wars and bloodshed on the planet.

«It's simple,— he said. — I will destroy all the weapons on Earth, and no one else will be able to fight.

— Great! People exclaimed.

A wave of the magic wand and the job is done.

For three days, peace reigned on the planet, while most of those who are inclined to fight were looking for and could not find their weapons. And when they realized that they had lost them forever, they made spears out of young trees and resumed their wars.

When this sad news reached the wizard, he said:

»Don't worry. I will destroy all the young trees, and these brawlers will no longer be able to fight.

After two or three days of fruitless searches for young trees suitable for making spears, belligerent people began to cut down giant trees, make clubs out of them, and resumed the bloodshed. The wizard destroyed all the big trees. Then people made knives and swords out of metal. He destroyed all the metal on the planet. People made slings and started throwing stones at each other. The stones also had to be destroyed. And then the supporters of peace sounded the alarm: of course, all the trees were gone, metals and stones were gone. How to live now, what to eat? Soon there will be no vegetation at all, and people will die without even fighting. No, this is not a solution to the problem.

The wizard was confused:

— I don't even know what to do now. I would destroy all of humanity, but unfortunately, it's not in my power yet!

The peacekeepers became discouraged, not knowing what to do. And then an intelligent child turned to the wizard.

«I know what you should do. Let people feel how others perceive their actions. If one causes pain to another, let him feel exactly the same pain, and if he brings joy to someone, then let him feel joy himself. Then, for sure, no one will hurt another, because they will immediately feel the pain themselves and will have to stop.

Everyone was imbued with the greatness of the thought expressed by the child's mouth, and the wizard brought his idea to life exactly. He brought back all the trees, metals and stones, and even weapons, which people soon converted into tools.

From that day on, no one on the planet caused suffering to another, because then he himself would have to experience pain. On the contrary, people started helping each other because they liked the feeling of joy they felt at the same time. And they lived in harmony and joy.