Jack Sparrow: [after Will draws his sword] Put it away, son. It's not worth you getting beat again.

Will Turner: You didn't beat me. You ignored the rules of engagement. In a fair fight, I'd kill you.

Jack Sparrow: Then that's not much incentive for me to fight fair, then, is it? [Jack turns the ship, hitting Will with the boom]

Jack Sparrow: Now as long as you're just hanging there, pay attention. The only rules that really matter are these: what a man can do and what a man can't do. For instance, you can accept that your father was a pirate and a good man or you can't. But pirate is in your blood, boy, so you'll have to square with that some day. And me, for example, I can let you drown, but I can't bring this ship into Tortuga all by me onesies, savvy? So, can you sail under the command of a pirate, or can you not?

--Pirates of the Caribbean

The pirate-specific stuff is a bit extraneous, but I've always thought this scene neatly captured the virtue of cold, calculating practicality. Not that "fairness" is never important to worry about, but when you're faced with a problem, do you care more about solving it, or arguing that your situation isn't fair? What can you do, and what can't you do? Reminds me of What do I want? What do I have? How can I best use the latter to get the former?