What can you learn from the summer intern?

My department has a summer intern with us right now, and he is so earnest. So enthusiastic. So smart. He's eager to get to work each day, fired up in anticipation of whatever assignment will fall to him that morning. He has pithy, inspirational statements, penned in red and black on 4-by-6-inch note cards, pinned up on the walls of his cube. -- the kind of stuff the rest of us learned in school, stuff that applies to our trade, stuff that we assume we know but probably need to remember.

When did the rest of us stop being like that?
I have worked for my main employer for 16 years, but I know that when I first came on board, as a fresh-out-of-college kid who was in love with the industry, I was like that. Eager, hungry, willing to do whatever was asked of me, reveling in the new experiences rather than stressing about supporting my family. He's not worrying about whether he's appreciated by his company; he's concerned with doing his best work every day, so that each opportunity leads to something more.

My career advice to my younger self reflects some of my current burnout, I think. And, to be brutally honest, our intern's enthusiasm highlights it even more. But if he wasn't spending the summer here, doing chirpy phone interviews and blessing everyone who sneezes, I wouldn't be aware of how far I've traveled from that old ideal -- or how my career might be better if I tried to recapture some of it.

Have you learned from experience, or do you think you could use a dose of intern-like optimism in your career?