So, What IS Happiness?
The research suggests that happiness is a combination of how satisfied you are with your life (for example, finding meaning in your work) and how good you feel on a day-to-day basis. Both of these are relatively stable—that is, our life changes, and our mood fluctuates, but our general happiness is more genetically determined than anything else. The good news is, with consistent effort, this can be offset. Think of it like you think about weight: if you eat how you want to and are as active as you want to be, your body will settle at a certain weight. But if you eat less than you'd like or exercise more, your weight will adjust accordingly. If that new diet or exercise regimen becomes part of your everyday life, then you'll stay at this new weight. If you go back to eating and exercising the way you used to, your weight will return to where it started. So it goes, too, with happiness.

In other words, you have the ability to control how you feel—and with consistent practice, you can form life-long habits for a more satisfying and fulfilling life.

Acacia Parks, Ph.D is Assistant Professor of Psychology at Hiram College, where she teaches classes on the science of happiness. Her research program focuses on the efficacy of positive interventions, and the psychological and behavioral characteristics of individuals who use them. She received her doctoral degree from the University of Pennsylvania. 

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What is Happiness? - Happy Definition - Happify Daily

What is happiness--and what is it not? People have agonized over this question for centuries, but only recently has science begun to weigh in on the debate.