The fable of the donkey and the tiger

One day, the donkey said to the tiger, “The grass is blue.” The tiger quickly and confidently replied, “No. The grass is green.” The donkey continued to insist that this was not true, and that he knew better. “The grass is blue!”, he shouted! The conversation quickly became heated, and then the two decided that it would be advantageous to consult someone to find out which of them was right.

They decided that the best animal to go to would be the lion, the King of the Jungle.

Arriving at the Lion's feet, the donkey immediately began to talk loudly: “Your Majesty... Your Majesty! Is it true that the grass is blue?” And the King replied immediately: “Yes. The grass is blue.” The donkey shouted even louder and exclaimed in a loud voice: “That tiger disagrees with me, Your Majesty. And that bothers me. Please punish him.” And the King declared: “The tiger will be punished with five years of silence.”

The donkey ran off, jumping for joy at his victory.

The tiger accepted his punishment, but before leaving, he asked His Majesty: “My King, why did you punish me? The grass is green.”

The lion replied after a few moments of silence, looking directly into the tiger's eyes: "Your punishment has nothing to do with the color of the grass. Your punishment is because I find it unacceptable that an animal as brave and intelligent as you should waste his time arguing with a donkey. And on top of all that, you also bother me with unimportant questions."

Moral of the story
The worst waste of time is arguing with a fool who doesn't care about the truth and is unwilling to listen to others or even change his mind. He is only concerned with being right and not losing his temper.