"I'm as light as a feather." In the 19th century, happiness was measured by money. Scrooge forced himself to believe that since he had money, he was happy. This was a common thought then, and it still is today. We try to measure success in life by wealth. At the end of the book, Scrooge realized that true happiness came from giving. This picture the lightness that he felt when he finally figured out how to become happy.