You waste years by not being able to waste hours.”

— Amos Tversky

One very important result of Kahneman and Tversky[‘s] work is demonstrating that people’s attitudes toward risks concerning gains may be quite different from their attitudes toward risks concerning losses.

excerpt from the article on Kahneman and Tversky’s Prospect Theory

You can find 7 paragraphs on “Kahneman and Tversky’s Prospect Theory” here.