When should we stop?

If someone knows when to stop arguing is a wiser one.

A story of a Tiger and a Donkey.

Once an argument started between a tiger and a donkey. The donkey was the dumbest animal in the whole forest, was saying that the sky colour is black. But the tiger was saying, "No, no, the sky colour is blue." 

The argument increased to such an extent that both were brought to the king Lion's court. After listening to both's argument, lion told to put the tiger behind the bars.

Tiger got shocked. He asked for mercy. He said, "My lord, you know that I am right. But still, you are giving me a punishment." The lion replied, "You are not punished because you were right or wrong about the fact. You are punished as you took courage and time to have an argument with the donkey."

So my friends, never argument with the one who doesn't deserve a chance. He is just enjoying his time by putting you into a bad situation. But you are wiser one, never fall into their trap.