I read this cautionary tale on UrbanMonk.net...
Once a renowned philosopher and moralist was travelling through Nasruddin’s village when he asked him where there was a good place to eat. Nasruddin suggested a place and the scholar, hungry for conversation, invited the Mullah to join him. Much obliged, Mullah Nasruddin accompanied the scholar to a nearby restaurant, where they asked the waiter about the special of the day.
“Fish! Fresh Fish!” replied the waiter.
“Bring us two,” they answered.
A few minutes later, the waiter brought out a large platter with two cooked fish on it, one of which was quite a bit smaller than the other. Without hesitating, Mullah Nasruddin took the larger of the fish and put in on his plate.
The scholar, giving Mullah Nasruddin a look of intense disbelief, proceeded to tell him that what he did was not only blatantly selfish, but violated the principles of almost every known moral, religious, and ethical system.
Mullah Nasruddin calmly listened to the philosopher’s extempore lecture patiently, and when he had finally exhausted his resources, Mullah Nasruddin said,
“Well, Sir, what would you have done?”
“I, being a conscientious human, would have taken the smaller fish for myself.”
“And here you are,” Mullah Nasruddin said, and placed the smaller fish on the gentleman’s plate.
Source: Evan’s Experientialism