With all due respect to resource depletion, global warming, and over-population, I have come to believe that the greatest environmental threat on the planet is our own minds. They are hungry little fuckers, these brains of ours. “We humans are an elsewhere,” wrote my friend Reg Saner, and boy are we ever. Walk across a college campus these days, as I do every day, and it’s a good bet you won’t make eye contact with a single one of the hundreds of students you pass. They are elsewhere, staring down into their machines, absorbed in urgent phone conversations, ears plugged and eyes glazed.  “The hunger of the imagination,” Samuel Johnson called this insatiable desire for more, a desire that springs from a dissatisfaction with what is and from the hope that what comes next will fulfill us in ways it never has before.

We have turned that same insatiable hunger on our own land, swallowing, goring, fracking, drilling so that we can have more and so that we can fuel the vehicles and machines that transport us elsewhere. One of the reasons I find it hard to be too fully moralistic about this behavior is that I share it. In my own work –which is writing — I am always hungry, wanting more and better, and I recognize in my own ambition the same never-sated animal that I see in others. Long ago, I sent a letter to a neighbor on Cape Cod who had built a monstrous trophy house. I wrote: “You’re obviously an ambitious man and in that we are alike. While your workers hammer away up on the hill, I hammer away at my keyboard. Like you, I dream of creating something big, something great, and like you, I sometimes feel that my passion for this controls me, and not me it.” So you see, I am not writing about hunger as an outsider, not Spock looking on puzzled at a world full of Kirks.

And yet that does not mean that I believe that this gets me, or us, off the hook, that we can let our inner Kirks run wild and shoot phasers in the air and make out with every Nurse Chapel they run across. The next sentences in my letter to my neighbor were these: “But we are more in control than we admit, than it’s fashionable to say these days. I don’t suggest the laughable premise that we are rational creatures, or that reason controls our lives. What I do suggest is that our imaginations can be nudged, and work best if nudged earthward.”

Let me give you a small example of what I mean, an example that, not incidentally, ties in nicely with our hunger metaphor. Like my neighbor of old, I like to build, and a year ago I built a writing shack down on the edge of my backyard near the tidal marsh. I liked the way the shack connected me to the marsh and the creek and therefore the ocean and my old coastal home in the north. And I liked, or at least claimed to like, the modesty of the place, its ramshackle look and its basic admission of impermanence, an 8-by-8-foot plywood structure with a screen door for a window, the whole place ready to be wiped out by the next hurricane. It was a perfect spot to collapse after a long day, to birdwatch and drink a beer and do nothing. Except of course for our old friend, the real serpent in the garden: the hungry mind. I soon set to colonizing the space, to building a desk, stocking it with writing pads, taping outlines of my next book to the plywood walls. What I had was nice, but I wanted more.

And then, to my own surprise, I stopped myself. It was a small miracle of restraint. I decided I didn’t want to turn the shack into another study, a mere workplace like the one I already have in the house. I ripped out the desk. I resolved that, as best I could, I would check ambition at the door when I entered the shack. I could scribble down notes, read a little, sure, but there would be no plans and no machines, at least for the short time I spent there each day. Then one day, when a friend and I were sipping beers and watching the sunset from the shack, the friend pointed up at the gap between the top of the door and the roof.

“You better screen that in soon,” he said. “Or the bugs will be terrible.”

I nodded and agreed, but I never did fix it. Consciously, not lazily. I decided this was one time I wasn’t going to give in to the constant need for “improvements.” I decided that, just this once, I didn’t need more or better.

Almost a year has passed since that conversation, and three weeks ago the world rewarded me for my decision not to improve. Two Carolina wrens, beautiful little birds that hop and strut about like field marshals as they dip and lift their cocked tails, decided to take advantage of the opening above the door. They set to building a nest right over the screen window. You can see it in this picture, resting against the stick my daughter found on one of our walks.

That would have been enough of a reward, but as it turned out, the world was just beginning to repay me. The wrens flew freely in and out to the nest, ignoring me though I was only four feet away. Then one day a couple of weeks ago I peeked into the nest and saw five eggs smaller than jelly beans. A couple of days later, I noticed that the female wren kept flying to the top of the door, but then, instead of flying to the nest as she usually did, she would fly back out, fussing in a nearby tree branch and on my roof.Something was different. I peeked into the nest and there they were: not birds exactly, but tiny living mouths. The four newborns were all maw. If Samuel Johnson had wanted a visual representation of his idea, here it was. Raw hunger.

My life feels better, more intense and elevated, having this new family around. Over the last two weeks the wrens and I have co-existed, though, feeling it was only good manners, I have spent less time in the shack, and each night I place the plywood cover over the screen window to keep the wind and rain out. When I do take a seat these days I witness the non-stop parade of feeding, performed by both the male and female, and I take notes in my journal of the type of insect or worm they have brought as an offering. The few minutes immediately after the feedings are the only time, outside of sleep, that the tiny birds stop pleading with their squeeze-toy squeaks and stop lifting their gaping mouths.

I won’t push my metaphor too hard. No doubt you get the point. Scientists might have a complex way of describing how the human brain operates, but I say it operates a whole lot like that nest full of birds. For my part, I am not ready to retire like a Zen monk to my shack. I am still hungry for things. A Pulitzer Prize would be nice, for instance, and after that maybe a Nobel. But right now I am enjoying a different sort of prize, and I can’t help but think this is a prize I’ve won by not doing something. And I’m encouraged by the fact that my mind is not in fact a nest of newborn birds, but a complex thing that can, every now and then, be controlled by something other than hunger.

It’s a small victory, I understand. But for the moment, it’s nice not to be elsewhere