"A joker is a little fool who is different from everyone else. He's not a club, diamond, heart, or spade. He's not an eight or a nine, a king or a jack. He is an outsider. He is placed in the same pack as the other cards, but he doesn't belong there. Therefore, he can be removed without anybody missing him."
— Jostein Gaarder (The Solitaire Mystery)

"Enough madness? Enough? And how do you measure madness? - The Joker"
— Grant Morrison (Batman: Arkham Asylum)

"Come here. Hey! Look at me. So I had a wife, beautiful, like you, who tells me I worry too much. Who tells me I ought to smile more. Who gambles and gets in deep with the sharks... Look at me! One day, they carve her face. And we have no money for surgeries. She can't take it. I just want to see her smile again, hm? I just want her to know that I don't care about the scars. So... I stick a razor in my mouth and do this...
[the Joker mimics slicing his mouth open with his tongue:] ...to myself. And you know what? She can't stand the sight of me! She leaves. Now I see the funny side. Now I'm always smiling! "
— Joker, Dark Knight

"There is always Joker to see through the delusion. Generation succeeds generation, but there is a fool walking the earth who is never ravaged by time."
— Jostein Gaarder (The Solitaire Mystery)

"No use, Joker! I knew you'd employ your sneezing powder, so I took an Anti-Allergy Pill! Instead of a SNEEZE, I've caught YOU, COLD!"
— Batman

"I took Gothom's white knight, and brought him down to our level. It wasn't hard because, madness, as you know, is like gravity; it just takes a little push."
— The Joker

"Si sabes hacerlo bien, no lo hagas gratis"
— Joker