“…We used this giving behavior as a proxy of prosocial behavior, as prior research has indicated that the expression of gratitude communicates a prosocial state (Grant & Gino, 2010;Tsang, 2006), acknowledges a responsibility to others (Alspach, 2009), and is associated with prosocial behavior such as providing help to strangers (Bartlett & DeSteno, 2006;Lazarus & Lazarus, 1994;Nowak & Roch, 2007). Accordingly, the act of writing thank you cards (or giving other gifts that show gratitude) is a proxy of prosocial behavior (Bradler & Neckermann, 2019;Carson, Muir, Clark, Wakely, & Chander, 2012;Froh et al, 2014). To further magnify the prosocial benefit that participants could bestow by giving thanks, participants learned that each thank you card that they gave to a recipient would give the recipient an added chance of winning a financial prize.…”