Current research reveals that mood and temperament have a large genetic component. In a 1996 study, University of Minnesota psychologists David Lykken and Auke Tellegen surveyed 732 pairs of identical twins and found them closely matched for adult happiness, regardless of whether they'd grown up together or apart. Such findings suggest that while we all experience ups and downs, our moods revolve around the emotional baselines or "set points" we're born with.

But even if we have an inherited range of happiness, are there some tools that we can learn in order to become happier and more satisfied with life?