My boyfriend and I had been dating for six months when we had the biggest fight of our relationship over the carbon footprint of a kerosene lamp. We had finished dinner in the cozy cabin of his sailboat and were about to begin a game of gin rummy to determine who would do the dishes when Doug stood up and banged his head on the kerosene lantern that dangled from the ceiling. He cursed as the lantern swung back and forth, dribbling kerosene onto the table.

I teased him because he did this almost every night, and then I wiped up the spill with a greasy rag and told him about a book I had been reading that listed kerosene as one of the dirtiest fossil fuels.

“I guess we should probably get a different lantern,” I said. “Maybe LED.”

“I love this lamp,” he said, leaning over me with a match to relight the wick. The lamp glowed brightly for a moment and then dimmed, its warm, yellow light filling the cabin.

Reading by the light of that kerosene lamp felt like going back in time. It imbued the cabin with nostalgia for an era I had never actually lived in, one where sailors navigated by the stars and burned whale oil for light.

I often wished I had a headlamp when Doug asked me to read aloud to him on the settee, my already poor eyesight undoubtedly worsening as I squinted under the dull glow of the lamp’s flickering wick, but it made everything feel so romantic. Reading Jack London stories to my lover, his head in my lap, the sailboat gently swaying with the waves, a hundred sea lions barking like dogs and belching under the distant pier — he was right, it wouldn’t be the same under LED.

Still, I told him about what I had read, how kerosene burns dirtier than almost any other fossil fuel and releases carbon dioxide and carbon monoxide, both terrible for indoor air quality. I told him about initiatives in Africa to replace kerosene lamps and stoves with solar power because the kerosene was poisoning people, giving them asthma and cancer and other awful illnesses.

I stumbled over some of the facts. I had listened to the book on tape, and though I had come away convinced that the lantern was bad, I was fuzzy on the details.

Doug sensed my hesitation, and I could hear the doubt in his voice when he said, “This really doesn’t seem dirty. There’s no soot, no smell. I think it’s fine.”

He sat down and began dealing the cards, but I pushed mine away. “It’s one of the dirtiest fossil fuels you could possibly burn. And it would be so easy to switch. You probably wouldn’t even notice, other than maybe we’d actually be able to see at night. Why are you so resistant to doing something that’s undeniably better for the earth?”

“I don’t care about the carbon footprint of one measly lantern,” he said. “I like it and I’m not going to get rid of it.”

“I hate that you’re so apathetic,” I said.

“You’re being ridiculous,” he said. There was a sharp, loud quality to his voice that I’d never heard before.

At that point, I uttered some sweeping generalization about privileged men and their lack of empathy, which made him furious that I was turning this into a judgment on his character, and that I had become worked up over nothing.

I tried to explain in six different ways why this was important to me and why the impending collapse of the natural world should be explanation enough for why I was upset, but I was doing it with rage in my voice and it was coming out all wrong.

He just kept repeating that he couldn’t understand why we were fighting over this, which made me even more frustrated that he wasn’t listening.

After an hour of fruitless back-and-forth, I was on the verge of tears. The situation felt entirely irreconcilable.

I knew I had taken it too far, yet I couldn’t stop. Doug is inarguably not apathetic when it comes to the environment. He has spent most of his adult life in the marine conservation field, working as a research diver gathering data on kelp forests and more recently working for National Geographic on their Pristine Seas Project, which has helped to create 26 of the largest marine reserves on the planet. It was our shared love of the natural world that brought us together in the first place: We met on a 20-day rafting trip through the Grand Canyon.

Still, I worried that the big issues of the world didn’t seem to affect Doug the same way that they affected me. Our political leanings were more or less aligned, and we shared similar dreams for the future, so I didn’t understand how he managed to go about his life without succumbing to the same existential dread and anger that plagued me.

It was a strange space for me to navigate, envying his capacity to be content in such a flawed world while also resenting the privilege that allowed him to feel that way. And instead of explaining all of this to him, I had picked a fight about a lamp.

It was at this point that Doug said it was possible the lantern wasn’t even fueled by kerosene. He knew he had bought the fuel at Ace Hardware but wasn’t sure what it was.

We shoved aside a couch cushion and pulled the fuel bottle from the storage compartment.

The words “Paraffin Lamp Oil” appeared in blocky green font across the front. When I Googled it, I learned that paraffin lamp oil is more refined than kerosene and also lacks many of kerosene’s impurities, making it relatively clean burning, with fewer pollutants, with the added benefit of not having the unpleasant odor of kerosene.

I looked at Doug, dumbfounded, and then stormed onto the deck to do the dishes. I had obviously lost, but when you spend an hour fighting about a kerosene lantern that isn’t even powered by kerosene, nobody wins.

I woke up the next morning feeling sheepish, my anger transformed into regret after a poor night’s sleep. I had to go to work, where I would spend the day performing tedious manual labor for a local land trust. We were working to restore native plant communities in the sensitive dune habitat of coastal California — a cause I certainly believed in, but the work itself would leave me with eight solitary hours to rehash every line of my ill-founded argument.

Doug offered to ferry me to the pier in the dinghy, but I told him to go back to sleep, that I’d take the paddle board.The sun had just crested the hills above the port, and the water was a glassy sheet. The fishermen had left before dawn and the tourists and beachgoers were yet to arrive, so the port was quiet aside from the small waves breaking on the sand and the occasional splash of a pelican. I tied off the paddle board and climbed the rickety ladder to the pier, where I pulled out my phone and texted him: “I’m sorry.”

Six months later, we were pointed south with wind in our sails, headed for Mexico. For eight weeks we sailed from Port San Luis to Puerto Vallarta, covering some 1,400 miles at an average moving speed of five miles per hour.

Along the way, Doug taught me how to estimate the wind speed, how to set a course and how to trim the sails. He taught me about kelp forests and the Madden-Julian Oscillation and the migratory patterns of whales. He taught me how to dive for scallops, how to load a spear gun and how to clean and filet a fish once I finally caught one. He made me jump overboard in the middle of the Pacific, where the water was 2,000 feet deep, to swim with rays.

As we slowly made our way south, Doug reminded me why I had joined the environmental movement in the first place. His eco-conscious life has been driven by his awe of the natural world — an awe so pure it’s almost childlike. And while mine started out that way, it had morphed over the years into something driven mostly by anger at what we’re losing.

Doug loves the ocean, and over the course of our voyage, he showed me a million reasons why. That made me love it and want to save it too. Efforts to preserve our planet are so often fueled by fury and fear, but they can also be fueled by hope. The simple, joyful life that Doug introduced me to at sea — powered by wind, sun and ocean currents — gave me hope, and it reminded me that there’s a better way to fight.

Alison Kaplan, who lives in Bishop, Calif., is a climbing ranger in Yosemite National Park.

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