Considering that Shatner has had an acting career for going on 70 years... I'd say that it's less ego and more hard work. Bill's take on life is to always say "Yes!" to anything that comes down the pike because saying "no" shuts any potential doors before they can be opened. Perhaps *that* is why he has been working consistently for so many years? From what I've seen of the man, he seems like a genuine human being who doesn't take himself too seriously. I absolutely love his documentaries.