Dear Kai and Leah,

I lie on my back on a wooden dock with a two-year-old Leah and gaze up at the stars. It’s late August and we’ve rented a cottage for a week to soak in the water, the sun, the lazy days of late summer. The two of you spend most of each day splashing on the beach and floating in an inflatable dinghy. But now it’s night, and with the nearest city a few hundred kilometers away, the clear sky dazzles us with silver sequins. This is my religion: billions of tiny dots, each one a massive ball of fire, each one lighting how many strange and wonderful worlds, each one so distant that we cannot see it as it is but only as it once was, a faded photograph fluttering across an incomprehensible expanse of space and time and possibility.

And then there’s us: a man and a girl lying here on these planks of wood, two tiny bodies on the edge of a lake in the middle of a forest on the crust of the Earth. In this universe we are nothing; two specks of dust in an endless cosmic cloud, a random and temporary grouping of atoms that will collapse and reform who knows how many times. We are humble, we are quiet. We look up. The trivia of daily life—and indeed, even great feats of human achievement—recede in the shadows of something so grand and mystical.

I want you to feel awestruck like I do. It is important to feel small sometimes, to feel the weight of reality, to recognize the scale of a challenge, to see where you fit and what you are up against. This is the case with climate change.

We are at something of a crossroads, this species of ours, and we have a few different paths we could take. We could keep going down the same path we’ve been walking so far, building and expanding without much thought about what it will cost us. This path leads to dangerous places: rising seas and droughts, wild storms and great migrations. There are other paths, safer paths, that require doing things differently, working together, taking a chance on some new ideas. I know, I know—I designed it so the second path sounds better. But even so, it turns out a lot of people just like what’s familiar. And it’s hard to move a few billion people anywhere, let alone somewhere that seems unfamiliar.

I’ll admit it: I’m not always optimistic. There are so many actors, so many divergent interests, so much money at stake, and such complexity that I sometimes fear for the things my great-grandchildren will see.

But we aren’t there yet, and I refuse to lose hope. For you, my children, I hope above all for a peaceful future, a future of collaboration and adaptation in which climate refugees are given safe harbor, resources are shared based on need, and all things of this Earth are treated with respect. You as individuals already have luck—to be born in a peaceful country to loving parents, to have not only your needs but also your desires met with ease, to live in an age of plumbing and electricity, internet and instant chat, to be able to eat a pomegranate when there’s snow on the ground.

I want you to understand your privilege as a responsibility. I want you to build in yourselves the skills this world needs. I want you to have everything but take nothing for granted. I want you to be prepared and to contribute because it is the right thing to do.

I don’t know that I meet these lofty expectations, but then isn’t a child supposed to surpass her parents? I try to contribute some beauty, some goodness, some new ideas to the stock of humanity and also the specific challenge of climate change. I work for a government that takes the climate challenge seriously, and I grapple with big policy issues every day. But bureaucracies move slowly—much slower than the emissions that pour out every time I start my car. What I do is not enough on its own, but it’s not nothing. I hope it amounts to something. And I hope you experience the triumph and opportunity of walking new paths, hand in hand, under a starry sky.