Poking into a sand dune last week, looking for shells, my niece uncovered a shark’s tooth, the first she’d ever found.

“Watch for pieces of eight and gold doubloons,” I told her, repeating something my mom, a tireless beachcomber, would say to us while we ambled along the Jersey shore, scouring the surf’s edge for treasures.

My niece and I were at Ocean City, N.J., one of the dozen or so beach towns that fill up each summer with Philadelphians. My parents took us there when we were children.

For young families, a giant sandbox next to a natural swimming pool remains the perfect vacation spot. Aside from rents, it’s cheap, and it’s easy. Moms and dads stretch out under beach umbrellas for the day and tykes wander almost anywhere they want. It’s reassuring to go back after 50 years and see that the place and the formula still work.

In this region, Jersey shore vacations are so sacred that people buy plaques on boardwalk park benches to memorialize times they’ve had on those beaches.  The plaques are inscribed with the names of family members, living and dead, who went on those trips. The sand, sun, breeze and the boardwalk cast a mighty spell, hardly tempered by ocean pollution, crowds and extra fees for parking and beach tags.

Biologist Wallace Nichols recently authored a book titled Blue Mind, on the therapeutic powers of water, its ability to provide feelings of “calm and well-being.” The book’s premise is that living near water can boost mental health and happiness, and that even just gazing into an aquarium can improve one’s attitude.

I don’t doubt Nichols’s thesis, but I would venture that there’s something else at work on us at seaside besides warm sand and the metronomic lullaby of rolling surf: It’s the wide blue horizon, a view of infinity, a landscape that sets loose imagination.

When we asked mom what was on the other side of the ocean, she would say, “England. France. Europe.”

She may as well have said the moon. With the exception of my grandfather’s all-expense-paid-trip to the Western Front in World War I, no one in my immediate family had ever been to Europe. It existed only in books or TV, but it was right there, out across the water, tantalizingly close and still hopelessly far away.

How far could it be? If you looked really hard and long, could you possibly see Europe on the opposite shore?

The ocean was literally the biggest thing we’d ever seen, consuming our view. Our lives at home were full of roads and houses and sidewalks and parks, objects that could be measured or at least viewed from front and back. But the ocean, seen from the shore, was as big as half the world.

Also, it magically churned an endless supply of waves, day and night, that inched up the beach then crawled back into the ocean. It gargled up strange critters like horseshoe crabs and jellyfish, even sharks – small toothless ones that occasionally swam into the shallows where we were swimming, and bigger, scary ones whose sightings would cause lifeguards to whistle everyone out of the water.

Albert Einstein reportedly said that imagination is more important than knowledge. If he actually made such a statement, I’m sure he wasn’t diminishing the importance of knowledge as much as making a point that there is so much more to know than what is known, and that our ability to know the unknown is limited only by our power to imagine what those things might be.

Knowledge is a statement, bounded by facts. Imagination is a question, bounded only our curiosity. At the Jersey shore, the ocean was our great question. Where did it come from? What did it contain? How far was it across? What was at its bottom?  Pieces of eight and gold doubloons cast from shipwrecks? Might they wash up on the beach?

Maybe.

A child quickly learns the meanings of “yes” and “no.” The ocean served up our first deep experience of “maybe,” a thought as delicious as any of the treats sold in shops along the boardwalk.

I suspect it’s still the Jersey shore’s biggest draw.

Read more from Tom here.