How we cite our quotes: All quotations are from The Dark Knight.
Quote #1
THE JOKER: I believe whatever doesn't kill you simply makes you… stranger.
This is a riff on a quote from philosopher Friedrich Nietzsche, who famously said "that which does not kill us makes us stronger." The Joker changes one little letter and alters the entire meaning. In his words, he's basically saying that if life doesn't kill you, it will drive you nuts, which is the only rule he seems to adhere to.
Quote #2
VIGILANTE: What gives you the right? What's the difference between you and me?
BATMAN: I'm not wearing hockey pads!
An early salvo in the movie's main philosophical meditation: what's the difference between good and evil? Why does Batman get to do what he does and nobody else get to join him? He has a very practical answer here, but the rule's going to be put to the test when the Joker enters the picture.
Quote #3
THE JOKER: Batman has no jurisdiction.
A little dig here from the Joker, suggesting that Batman breaks the rules that he finds inconvenient, too. Considering the context—he's warning the mob that Batman is going to bring them down—it also shows the Joker's admiration for the power that kind of lawlessness can bring. That's scary, man.
Quote #4
ALFRED: Some men aren't looking for anything logical. They can't be bought, bullied, reasoned or negotiated with. Some men just want to watch the world burn.
Rules can be imprisoning when you think of them as the only way to do things. Here Alfred points out that the Joker's so dangerous in part because Bruce is looking at him through a particular set of expectations… which are basically unspoken rules. Yeah, the Joker likes breaking those too.
Quote #5
BATMAN: I want the Joker.
MARONI: From one professional to another, if you're trying to scare somebody, pick another spot. From this height, the fall wouldn't kill me.
BATMAN: I'm counting on it.
This is a great straight-up look at how the Batman adheres to some rules (don't kill anyone) while cheerfully breaking others (don't menace Mafia bosses if you're not a cop).
Quote #6
THE JOKER: See, their morals, their code... it's a bad joke. Dropped at the first sign of trouble. They're only as good as the world allows them to be. I'll show you, when the chips are down, these...these civilized people? They'll eat each other. See, I'm not a monster, I'm just ahead of the curve.
Here's the really scary part: the Joker isn't just interested in flaunting the rules of civilization: he wants civilization to give them up too. Even worse, he thinks it's inevitable, and accordingly, he's going to make it happen. Sleep tight, kids.
Quote #7
BATMAN: I have one rule.
THE JOKER: Oh, then that's the rule you'll have to break to know the truth.
BATMAN: Which is?
THE JOKER: The only sensible way to live in this world is without rules.
Here, Batman and the Joker define the real terms for their conflict. The Batman won't kill anyone. That's it. And if the Joker can induce him to kill someone, even if it's the Joker himself, then Batman has perfectly proven the Joker's point. Easy on that trigger finger Bats; you're playing for keeps here.
Quote #8
THE JOKER: You know what I've noticed? Nobody panics if things go "according to plan…" even if that plan is horrifying. If tomorrow, I tell the press that, like, a gang-banger will get shot, or a truckload of soldiers will be blown up, nobody panics because it's all "part of the plan." But if I say that one little old mayor will die…well then everyone loses their minds!
For a crazy man, he kind of has a point here. Sometimes, the rules become more important than the good things they're supposed to make happen. Again, it's the "destroying the village in order to save it" thing. Sometimes we have to break the rules to do the right thing, and if we do, then how do we even know what the right thing is? It's a thorny question, though most of us prefer to contemplate it without burning hospitals down or driving public officials crazy.
Quote #9
THE JOKER: I think you and I are destined to do this forever.
The Joker implies that this is how it's going to be going forward, which is another way of saying "these are the new rules, that you and I have created through this little battle of wills." Even he can't escape the need for them sometimes.