In the end, people don't view their life as merely the average of all its moments—which, after all, is mostly nothing much plus some sleep. For human beings, life is meaningful because it is a story. A story has a sense of a whole, and its arc is determined by the significant moments, the ones where something happens. Measurements of people's minute-by-minute levels of pleasure and pain miss this fundamental aspect of human existence. A seemingly happy life maybe empty. A seemingly difficult life may be devoted to a great cause. We have purposes larger than ourselves.