A man had a horse and a donkey.
One day they were both on their way to the city, the donkey, feeling tired, said to the horse:
Take a part of my burden if you're interested in my life.
The horse playing deaf didn't say anything to the donkey.
Hours later, the donkey fell victim to fatigue, and died right there.
Then the owner threw all the load up the horse, even the donkey's skin and the horse, sighing, said:
What a bad luck I have!  If I would've helped the donkey I wouldn't have to carry everything even the skin of the donkey on my back. 

The moral is: Everytime you don't help somebody who asks for help,actually you're hurting yourself.