"I wouldn't trade it for the world!"  And you know this because you've actually been offered the world, and you turned it down?  Seriously, you're never going to offered the world for anything.  So saying you wouldn't take what you're never going to get is just silly.  Me?  I'm never marrying the Queen of England.  I don't care how much she begs.

And I don't care what the "it" is that you wouldn't trade the world for.  I'm betting a million in cash would make you think twice.  "I know, sweetheart, we all love Frisky, but that nice man over there has offered us all this money...and... well... Frisky is just a hamster.  But don't worry.  You won't miss him.  You're going, too!"

Here's the thing.  You can't predict the future.  Well... you can.  But it's just a guess, or maybe a hope, not that there's much difference between the two.  Would you be the one to act heroically?  Would you stand up for what is right even it it meant dying?  Would you tell that person no and go home to your family?  Would you trade your child's dog for a new truck?  Your wife for a hunting dog?  We'd all like to think we'd do the right thing at the right time, but until that time comes, until the money's on the table, you simply cannot know.