Wonder Why You're Sad so Often?

Probably because you spend too much time wondering about things.

"A human mind is a wandering mind, and a wandering mind is an unhappy mind," concluded Matthew A. Killingsworth and Daniel T. Gilbert, the authors of [a] study which was published in the Nov. 12 issue of "Science." "The ability to think about what is not happening is a cognitive achievement that comes at an emotional cost."

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Just what sorts of places does the mind wander? Reminiscing (and ruing) past events, looking forward to (or fearing) things that might happen in the future.

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[People] were least happy when working, resting, or using a home computer. (Captain's note: this means almost certainly that you're unhappy this very moment, doesn't it? It's ok to cry now if you need to.)

"Mind-wandering is an excellent predictor of people's happiness," Killingsworth said in the statement. "In fact, how often our minds leave the present and where they tend to go is a better predictor of our happiness than the activities in which we are engaged."

[CBS News]