Feeling grumpy? Don't feel bad - it may actually be good for you:
An Australian psychology expert who has been studying emotions has found being grumpy makes us think more clearly.
In contrast to those annoying happy types, miserable people are better at decision-making and less gullible, his experiments showed.
While cheerfulness fosters creativity, gloominess breeds attentiveness and careful thinking, Professor Joe Forgas told Australian Science Magazine.
I was about to object and say that depressed people can't be good decision-makers (b/c of the self-absorption factor), but your post isn't really about depression. I mean, grumpiness does not equal depression. Right?
Episodic depression may help people come up with answers and solve problems, but believe me, chronic depression doesn't help you at all. Even when you come up with answers you don't act on them, and most people with chronic depression are so pessimistic that they're too busy thinking of ways stuff could go wrong...myself included. It takes a lot of effort to think in a positive and productive manner and get things done.