I had my son with me for a little while at work today, so when I got a break, I took him out to a large lawn on the other side of the parking lot from my office. I work underground—literally—so some fresh air and sunshine always sounds like a good idea after I’ve been staring at a screen for a couple of hours.

The lawn slopes a tad toward a large white-brick wall, on the other side of which is a jungle-like tangle of plants covering an even steeper slope that leads to a creek.

When I freed my boy from the carrier in which I’d imprisoned him, he ran a few delighted steps on the grass, then headed straight for the wall and tried to climb it.

It’s what I would have done at his age. It’s what I still do, in fact, when faced with similar surroundings.

But why?

My son had a football-field-sized swath of green (proportionally to him, anyway) on which to walk, run, roll, whatever. There were plenty of dead leaves to kick around and crunch, sticks for waving and poking into eyes and nostrils, and little green and white pellets that were probably fertilizer, but looked like candy. But despite this carpet of riches, he focused on the wall.

He’s a bit young for strategy, I think, so I ruled out any desire of his to take the high ground and thereby gain a tactical advantage over his enemies.

Then I had two simultaneous thoughts. Try to read the next two lines as one single, overlapping sentence, to best approximate what was going on inside my head:

It must be our nature to not be content with what we have, to ignore what’s in front of us while we try to escape to what we imagine must be something more and better despite not knowing what it is.

And:

I am amazed at humanity’s fearless urge to explore this world, to not be content with the known and the safe and the carefully manicured and curated, to strive despite ferocious odds against the barriers we see or sense but do not accept.

Yes, I’m that eloquent in my head, even on the fly.

The opposing feelings made me laugh (again, in my head—I probably looked like a crazy person to passersby). Something as simple as my son trying to scale a wall more than double his height made me at once frustrated and proud, for him and for all people.

There is a tension here, in this life. Even at our happiest, I believe, we are still, however slightly, yearning for something more. The Not Yet. We are still looking to what Aslan, in the Chronicles of Narnia books, would call “further up and further in.” To believe in God—the Christian God, anyway, as I do—is to embrace (or at least be OK with) paradox. This life is great, on the whole, but there’s still something on the other side of that wall. I can be happy and discontent, grateful and dissatisfied. Here and there. Or wanting to be in one. Or the other. Or both.

Faced with such mysteries unfolding unexpectedly in the middle of a workday, I scooped up my son, handed him a stick too long to cause any eye-gouging damage (on himself, anyway), and plunked him on top of the wall. He refused to even sit on it without me holding his shoulders or hips—at first. But he soon raised himself to standing, and, with my help, leaned out over the other side to poke at leaves and branches growing close enough for him to reach.

Then he took my hand and walked the length of the wall, never once looking down at the ground on either side.