
How Gratitude Beats Materialism — by Jason Marsh & Dacher Keltner
http://greatergood.berkeley.edu/article ... _happiness

Welles
Perhaps the most widely tested of these is the “gratitude journal,” in which people write down five things for which they’re grateful. In some studies, they journal on their own every day for two weeks; in others, they write only once a week for six weeks or longer.