There are smart people, and then there are confident people. While some people possess both smarts and self-confidence, others may have or exhibit only one of these attributes.  There's no question that politicians like Donald Trump, Ted Cruz, Hillary Clinton, and Barack Obama are bright, self-assured people. Connections notwithstanding, they would otherwise not have made it to the big stage.  Of course, people are at their best when they embody both of these characteristics. You could be the smartest guy in the world, but if you don't make your points with some level of conviction, no one would ever know it. People won't believe what you're saying -- no matter how ground-breaking or erudite -- if you don't sound sure of yourself. At the same time, being gregarious won't get you far unless whatever you're discussing has substance. Spouting off nonsense undercuts any confidence you may bring to the table because, after a while, people will simply w...