A very old rich man was in the hospital awaiting death. He called for his two sons to see him before he died. He said to his sons, "I want you each to find a horse and ride it to the next town. The owner of the horse that arrives last will recieve my entire fortune." The sons were both very confused as to how they would get to the next town last.

They both started their ride to the next town, each trying desperately to go slower than the other. Just when they were about to give up, they both had an idea of how to inherit the money.

What was it?