Running in Place

The hedonic treadmill (also called hedonic adaptation) describes a pattern: after any positive or negative life change, people tend to return to a relatively stable baseline level of happiness. You get a raise, feel great for weeks, then it becomes the new normal.

The research is striking. Lottery winners, on average, are not significantly happier than non-winners one year after their windfall. People who become paraplegic report surprisingly high life satisfaction after the initial adjustment period.