It happened once that a traveller hired a wagon driver to take him from one town to another, and it was a day of bitterly cold weather.  The traveler, in spite of a thick coat and a scarf wrapped around his head, sat shivering in the wagon as they rolled slowly through the frozen countryside. He noticed, though, that the driver, only wearing a poor, thin jacket, did not seem to mind the cold.

In his mind, the traveller searched for some possible explanation for this: perhaps the driver ate some special diet?  Or was he an adept of some esoteric system known only to his tribe, handed down from generation to generation?  Or could it be that sitting nearer to the horse which was pulling the wagon, he received some extra heat?  Somehow none of his ideas seemed right.  Finally, he asked, “Why is it, driver, that you do not suffer from the cold as I do?”

The driver glanced back for a moment at the clothes of his passenger.  “Excellency,” he said, “you can afford to be uncomfortable.  As I have no money, feeling cold is beyond my means.”