Never Underestimate the Power of a Positive Mental Attitude.

This link links positive thinking to longer life and enjoying life more. God through Paul instructs the Philippians and us to be positive thinkers in Philippians 4 verse 8. It reads: Finally, brothers, whatever is true, whatever is noble, whatever is right, whatever is pure, whatever is lovely, whatever is admirable—if anything is excellent or praiseworthy—think about such things.

Notice that our thoughts don't have to have anything to do with our abilities, talents, opportunities or lack of opportunities that are perceived or real.