You're sitting next to her, on a rocky peak above the beach. If you don't look to closely, it's not hard to imagine the waves are washing over seashells and rocks instead of broken bottles and rust.
"A tidepool is small. It has boundaries. You can know every inch of it, who lives there, the rules it follows, its balance. If you live there, it's your whole world, and you know how the world works.
"And then the tide comes in, and you're swept into the ocean. And you don't know where you are, or if you'll ever see anything familiar again. You don't know the rules. You don't know how to live. There are no boundaries, any more.
"And maybe the tide goes back out, and you find yourself in another tide pool. And you try to pretend it's the way it was before, even though it's a different world, and it's not the one you know.
"And maybe you're caught in a riptide, devoured by the open sea, never to return. You'll never have a world you can make sense of again." Her gaze is steady, far out to the horizon. A gull glides overhead, silent amidst the sound of surf.
"And maybe you end up like us. Tossed onto dry land. Looking down at the tidepools and wondering how we ever survived."
"It's pretty," you say. There are tide pools below, little rocky things. You can't tell if anything's alive in them, not from up here. "But it's not quite right. If I were a fish in a tidepool, I'd die stranded on dry land."
She doesn't shift her gaze. "What is death, if not a world unknown? And what is life, except to hope to that you're a crab?"