Is it better to be an optimist or a pessimist?

This is Kim.....I wonder, could the answer to the question, optimist or pessimist be neither?  Think about it.  The optimist sees the glass half full, while the pessimist sees the glass half empty.  Essentially, an optimist is likely positive in expectation about the future and a pessimist is likely negative in expectation about the future.  Common to both is thinking about the unknown future.  Is either then in the present moment?   

Preston and I were 'competing' with one another just last night, having a lengthy debate about this very topic and its relationship to happiness and best outcomes in life.  Our oldest, Caleb, was stressing over a math quiz the next day, telling us he just felt it in his gut that despite doing his best to study and prepare, he wasn't going to do well.  Preston offered that if he chose to think that way already, this would negatively impact the likely result.  He argued that if you say you won't do well, guess what, you won't.  Why not consider choosing to embrace a different mindset, where thinking positively about his ability to do well on the quiz would increase the likelihood that Caleb's outcome would turn out positive?  I argued that it was best to be a happy pessimist, because they imagine all the things that could possibly go wrong and when they turn out right, or at very least better than expected, they are pleasantly surprised.  I wondered if the optimist is constantly let down, because things never go as well as imagined?  We looked up all kinds of research to support both points of view before realizing that the danger for both optimists and pessimists were being wrapped up in the future and not present. 

I wonder, instead of seeing the glass half full as an optimist, or half empty as a pessimist, why not consider that the glass "just is"?  Why be worried at all about what the future holds?  Why not simply choose to be "Nowist"!?  The present moment is all we can be sure of anyway.