Gratitude, thankfulness, or appreciation is a positive emotion or attitude in acknowledgment of a benefit that one has received or will receive. The systematic study of gratitude within psychology only began around the year 2000, possibly because psychology has traditionally been focused more on understanding distress rather than understanding positive emotions. However, with the advent of the positive psychology movement, gratitude has become a mainstream focus of psychological research. The study of gratitude within psychology has focused on the understanding of the short term experience of the emotion, individual differences in how frequently people feel gratitude, and the relationship between these two aspects.
Gratitude is not the same as indebtedness. While both emotions occur following help, indebtedness occurs when a person perceives that they are under an obligation to make some repayment of compensation for the aid. The emotions lead to different actions; indebtedness motivates the recipient of the aid to avoid the person who has helped them, whereas gratitude motivates the recipient to seek out their benefactor and to improve their relationship with them.
Gratitude may also serve to reinforce future prosocial behavior in benefactors. For example, one experiment found that customers of a jewelry store who were called and thanked showed a subsequent 70% increase in purchases. In comparison, customers who were thanked and told about a sale showed only a 30% increase in purchases, and customers who were not called at all did not show any increase. In another study, regular patrons of a restaurant gave bigger tips when servers wrote “Thank you” on their checks.
A large body of recent work has suggested that people who are more grateful have higher levels of well-being. Grateful people are happier, less depressed, less stressed, and more satisfied with their lives and social relationships. Grateful people also have higher levels of control of their environments, personal growth, purpose in life, and self acceptance. Grateful people also have less negative coping strategies, being less likely to try to avoid a problem, or deny there is a problem, blame themselves, or cope through substance use. Grateful people sleep better, and this seems to be because they think less negative and more positive thoughts just before going to sleep.