Psychology researchers discuss their findings in a New York Times op-ed piece.
The take-home advice:
Positive thinking fools our minds into perceiving that we’ve already attained our goal, slackening our readiness to pursue it.
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What does work better is a hybrid approach that combines positive thinking with “realism.” Here’s how it works. Think of a wish. For a few minutes, imagine the wish coming true, letting your mind wander and drift where it will. Then shift gears. Spend a few more minutes imagining the obstacles that stand in the way of realizing your wish.
This simple process, which my colleagues and I call “mental contrasting,” has produced powerful results in laboratory experiments. When participants have performed mental contrasting with reasonable, potentially attainable wishes, they have come away more energized and achieved better results compared with participants who either positively fantasized or dwelt on the obstacles.
When participants have performed mental contrasting with wishes that are not reasonable or attainable, they have disengaged more from these wishes. Mental contrasting spurs us on when it makes sense to pursue a wish, and lets us abandon wishes more readily when it doesn’t, so that we can go after other, more reasonable ambitions.
"Positive thinking" is not a very precise phrase. In this case it seems like it's used to mean "daydreaming".
I'm more convinced that the kind of positive thinking described in this article is useful: http://tynan.com/how-to-be-happy-always (If anyone has a convincing rebuttal to it, I'm interested.)
I like that article. For people capable of thinking about what methods make humans happy, it seems unlikely that simply performing any feel-good method will overcome barriers as difficult as what happiness means or what use is happiness anyway. They might improve one's outlook in the short term, or provide an easier platform to help answer those questions, but to me the notion that therapy works because of therapists (a sort of research supported idea if I recall correctly) corresponds well to the intuition that humans are just too wrapped up for overly ... (read more)