A couple of days ago Steven Spielberg delivered a modest, unassuming, mild-mannered commencement speech to Harvard University’s graduating class of ’16. A less secure man would’ve tried to present a cultivated, ultra-brainy front in deference to Harvard’s ivy-league reputation, but he played it simple and straight. “I am not the world’s best educated film director,” he more or less said, “but I’ve been around and done pretty well for myself and here’s what I believe is important.” And that’s fine.

He urged the students to find “a villain to vanquish” when in reality the thing they’ll need to fight the most in their lives will be their own tendencies toward selfishness; ditto that of their friends, neighbors and business colleagues.

“My job is to create a world that lasts two hours,” Spielberg said. “Your job is to create a world that lasts forever.” I’m presuming he meant that they need to do something creative and visionary with their lives in their 20s and 30s while the clay is still moldable. The best of them will continue their dynamic activity into middle and old age, but most of them won’t — let’s face it.

Best remark: “We are a nation of immigrants, at least for now.”

I don’t know what “create a world that lasts forever” could mean. We’re only around for 60 or 65 years after we graduate and then our kids and grandkids take over with ideas of their own. (“You did fine in your day, dad, but we’re running the show now.”) The best we can hope to do is maybe stir some fresh ripples or currents in the lake, and maybe, if we’re truly exceptional, find a way to change the game and lift all boats. The main thing is to not just dog-paddle along.

One no-big-deal observation: Spielberg comes to Harvard University in a nice dark gray suit and a somber tie, and he wears light gray cross-training shoes with white stripes along the sole. Older guys like to wear comfort shoes, I get that, but I would have changed into some black Bruno Magli lace-ups just before the ceremony began and then change back into the dork shoes after it’s over. But that’s Spielberg for you.