Negative emotions are a call to action, positive emotions are rewards for taking the proper action

When it comes down to it, if you feel crappy it’s because your brain is telling you that there’s a problem that’s unaddressed or unresolved. In other words, negative emotions are a call to action.  When you feel them, it’s because you’re supposed to do something.  Positive emotions, on the other hand, are rewards for taking the proper action.  When you feel them, life seems simple and there is nothing else to do but enjoy it.  Then, like everything else, the positive emotions go away, because more problems inevitably emerge.