It's why I drew the distinction between Honest Abe the man and Abraham Lincoln Vampire Hunter. Or the Lincoln who met Captain Kirk. What is it about the latter characters, taken at face value, that allows us to dismiss their historical existence with such certainty?
At the age of five, Skagra decided emphatically that God did not exist. This revelation tends to make most people in the universe who have it react in one of two ways - with relief or with despair. Only Skagra responded to it by thinking, 'Wait a second. That means there's a situation vacant.'