Scorpion and a fox

One day scorpion was heading on its way and stumbled upon the river.
That was an impassable obstacle for it, and so it started thinking how to go across.

Conveniently, at that time, the fox was coming to the river, too, planning to go across.

“Please allow me to jump on your back and carry me across the river. I’ll be in debt to you always” – said the scorpion.

“Why should I do that ?” – replied the fox – “you are going to sting me and I’m going to die”

“Please help me” , said the scorpion, “I’m not going to sting you, because if I do, you’ll die and I am going to drown, too”.

“Hm… you have the point” – fox replied. “All right, I’ll help you. Here. Jump on my back.”

The scorpion jumped on the foxes back and in the next moment, the fox started swimming over the river.
When they were half way across, scorpion suddenly stung the fox.

Feeling that her life is fading out, with her last breath, fox asked the scorpion:
“Why have you done that? Now you are going to die, too…”
“Yes, I know… but this is my instinct and it is a part of my nature. I found that I can not go against that” – scorpion replied.

They both died.