"As Batman hunts the Joker through a dilapidated circus that resembles the accumulation of a lifetime of bad trips, the Joker realizes the two foes had a common starting point. He asks Batman, ‘You had a bad day once, am I right? I know I am. I can tell. You had a bad day and everything changed. Why else would you dress up like a flying rat?’ The difference, of course, is the path that each man chose in coming to terms with his ‘one bad day.’"—Frank Verano in What is a Superhero?
Image credit: The Dark Knight Tumblr. Used for purposes of illustration.

"As Batman hunts the Joker through a dilapidated circus that resembles the accumulation of a lifetime of bad trips, the Joker realizes the two foes had a common starting point. He asks Batman, ‘You had a bad day once, am I right? I know I am. I can tell. You had a bad day and everything changed. Why else would you dress up like a flying rat?’ The difference, of course, is the path that each man chose in coming to terms with his ‘one bad day.’"
Frank Verano in What is a Superhero?

Image credit: The Dark Knight Tumblr. Used for purposes of illustration.