"HAVE YOU EVER BEEN DEPRESSED or anything?" I ask.

We've just made what felt like a significant turn. We'd been on the same road for a while. We turned at a stop sign, not at a light. Left. There are no traffic lights out here.

"Sorry, that was out of the blue. I'm just thinking."

"About what?"

For years, my life has been flat. I'm not sure how else to describe it. I've never admitted it before. I'm not depressed, I don't think. That's not what I'm saying. Just flat, listless. So much has felt accidental, unnecessary, arbitrary. It's been lacking a dimension. Something seems to be missing.

"Sometimes, I feel sad for no apparent reason," I say. "Does this happen to you?"

"Not particularly, I don't think," he says. "I used to worry when I was kid."

"Worry?"

"Yeah, like I would worry about insignificant things. Some people, strangers, might worry me. I had trouble sleeping. I'd get stomachaches."

"How old were you then?"

"Young. Maybe eight, nine. When it would get bad, my mom would make what she called 'kids tea,' which was pretty much all milk and sugar, and we'd sit and talk."

"About what?"

"Usually about what I'd been worried about."

"Do you remember anything specific?"

"I never worried about dying, but I did worry about people in my family dying. Mostly it was abstract fears. For a while I worried one of my limbs might fall off."

"Really?"

"Yeah, we had sheep at our farm, lambs. A day or two after a lamb was born, Dad would put special rubber bands around its tail. They're very tight, enough to stop the blood flow. After a few days, the tail would just fall off. It's not painful for the lambs; they don't even know what's happening.

"Every so often, as a kid, I'd be out in the fields and I'd find a severed lamb tail. I started to wonder if the same thing could happen to me. What if the sleeves on a shirt or a pair of socks were slightly too tight? And what if I slept with my socks on and I woke up in the middle of the night and my foot had fallen off? It made me worry, too, about what's important. Like, why isn't the tail an important part of the lamb? How much of you can fall off before something important is lost? Right?"

"I can see how that might be unnerving."

"Sorry. That was a very long answer to your question. So to answer, I would say that no, I'm not depressed."

"But sad?"

"Sure."

"Why is that-how is that different?"

"Depression is a serious illness. It's physically painful, debilitating. And you can't just decide to get over it in the same way you can't just decide to get over cancer. Sadness is a normal human condition, no different from happiness. You wouldn't think of happiness as an illness. Sadness and happiness need each other. To exist, each relies on the other, is what I mean."

"It seems like more people, if not depressed, are unhappy these days. Would you agree?"

"I'm not sure I'd say that. It does seem like there's more opportunity to reflect on sadness and feelings of inadequacy, and also a pressure to be happy all the time. Which is impossible."

"That's what I mean. We live in a sad time, which doesn't make sense to me. Why is that? Are there more sad people around now than there used to be?"

"There are many around the university, students and profs whose biggest concern each day-and I'm not exaggerating-is how to burn the proper number of calories for their specific body type based on diet and amount of strenuous exercise. Think about that in the context of human history. Talk about sad.

"There's something about modernity and what we value now. Our shift in morality. Is there a general lack of compa.s.sion? Of interest in others? In connections? It's all related. How are we supposed to achieve a feeling of significance and purpose without feeling a link to something bigger than our own lives? The more I think about it, the more it seems happiness and fulfillment rely on the presence of others, even just one other. The same way sadness requires happiness, and vice versa. Alone is . . ."

"I know what you mean," I say.

"There's an old example that gets used in first-year philosophy. It's about context. It goes like this: Todd has a small plant in his room with red leaves. He decides he doesn't like the look of it and wants his plant to look like the other plants in his house. So he very carefully paints each leaf green. After the paint dries, you can't tell that the plant has been painted. It just looks green. Are you with me?"

"Yeah."

"The next day he gets a call from his friend. She's a plant biologist and asks if he has a green plant she can borrow to do some tests on. He says no. The next day, another friend, this time an artist, calls to ask if he has a green plant she can use as a model for a new painting. He says yes. He's asked the same question twice and gives opposite answers, and each time he's being honest."

"I see what you mean."

Another turn, this time at a four-way stop.

"It seems to me that in the context of life and existing and people and relationships and work, being sad is one correct answer. It's truthful. Both are right answers. The more we tell ourselves that we should always be happy, that happiness is an end in itself, the worse it gets. And by the way, this isn't a very original thought or anything. You know I'm not trying to be brilliant right now, right? We're just talking."

"We're communicating," I say. "We're thinking."

IT'S MY PHONE THAT BREAKS the silence, ringing from my bag. Again.

"Sorry," I say, reaching down to retrieve it. It's my number on the screen. "My friend again."

"Maybe you should answer it this time."

"I really don't feel like talking. She'll stop calling eventually. I'm sure it's nothing."

I put the phone in my bag but pick it up again when it beeps. Two new messages. This time, I'm glad the volume of the radio is high. I don't want Jake to hear the messages. But the Caller's not talking in the first message. It's just sounds, noises, running water. In the second, it's more running water and I can hear him walking, footsteps, and what sounds like hinges, a door closing. It's him. It has to be.

"Anything important?" Jake asks.

"No." I hope to sound casual, but I can feel my face growing warmer.

I'm going to have to deal with this when we get back, tell someone, anyone, about the Caller. But now, if I do say something to Jake, I'll also have to tell him I've been lying. It can't keep going on. Not like this. Not anymore. The running water continues. I'm not sure why he's doing this to me.

"Really? Not important? Two calls, not even texts, in a row. Seems important, no?"

"People are dramatic sometimes," I say. "I'll talk to her tomorrow. My phone's about to die anyway."

I THINK JAKE'S LAST GIRLFRIEND was a grad student in another department. I've seen her around. She's cute: athletic, with blond hair. A runner. He definitely dated her. He says they're still friends. Not close friends. They don't hang out. But he said they had coffee a week before we met at the pub. I probably sound jealous. I'm not. I'm curious. I'm also not a runner.

It's weird, but I'd like to talk to her. I'd like to sit down with a pot of tea and ask her about Jake. I'd like to know why they started dating. What was it about him that attracted her? I'd like to know why it didn't last. Did she end things, or did Jake? If it was her, for how long was she thinking of ending things? Doesn't this seem like a reasonable idea, chatting with a new partner's ex?

I've asked him about her a few times. He's coy. He doesn't say much. He just says their relationship wasn't long or very serious. That's why it's her I have to talk to. To hear her side.

We're alone in a car in the middle of nowhere. Now seems as good a time as any.

"So, how did it end?" I say. "With your last girlfriend, I mean."

"It never really started," he says. "It was minor and temporary."

"But you didn't start out thinking that."

"It didn't start out any more serious than when it ended."

"Why didn't it last?"

"It wasn't real."

"How do you know?"

"You always know," he says.

"But how do we know when a relationship becomes real?"

"Are you asking in general, or about that relationship specifically?"

"That one."

"There was no dependency. Dependency equates to seriousness."

"I'm not sure I agree," I said. "What about real? How do you know when something's real?"

"What is real?" he says. "It's real when there are stakes, when something's on the line."

For a while we don't say anything.

"Do you remember me telling you about the woman who lives across the street?" I ask.

I think we must be getting close to the farm. Jake hasn't confirmed we are, but we've been driving for a while. Must be close to two hours.

"Who?"

"The older woman from across the street. Remember?"

"I think so, yeah," he says noncommittally.

"She was saying how she and her husband have stopped sleeping together."

"Hmm."

"I don't mean not having s.e.x. I mean have stopped sleeping in the same bed at night. They both decided a good night's sleep trumps any benefits to sleeping in the same bed. They want their own sleeping s.p.a.ce. They don't want to hear another person snoring or feel them turn over. She said her husband's a pretty vicious snorer."

I find this very sad.

"It seems reasonable that if one person is disruptive, sleeping alone would be an option."

"You think? We spend almost half our lives asleep."

"That could be an argument for why it's best to find the optimal sleeping situation. It's an option, that's all I'm saying."

"But you're not just sleeping. You're aware of the other person."

"You are just sleeping," he insists.

"You're never just sleeping," I say. "Not even when you're asleep."

"You've lost me."

Jake signals and makes a left turn. This new road is smaller. It's definitely not a main road. This is a back road.

"Aren't you aware of me when we're sleeping?"

"I mean, I don't know. I'm asleep."

"I'm aware of you," I say.

TWO NIGHTS AGO, I COULDN'T sleep. Yet again. I've been thinking too much for weeks. Jake slept over for the third night in a row. I actually like sleeping in bed with someone. Sleeping beside someone. Jake was sound asleep, not snoring, but his breathing was unmistakably close. Right there.

I think what I want is for someone to know me. Really know me. Know me better than anyone else and maybe even me. Isn't that why we commit to another? It's not for s.e.x. If it were for s.e.x, we wouldn't marry one person. We'd just keep finding new partners. We commit for many reasons, I know, but the more I think about it, the more I think long-term relationships are for getting to know someone. I want someone to know me, really know me, almost like that person could get into my head. What would that feel like? To have access, to know what it's like in someone else's head. To rely on someone else, have him rely on you. That's not a biological connection like the one between parents and children. This kind of relationship would be chosen. It would be something cooler, harder to achieve than one built on biology and shared genetics.

I think that's it. Maybe that's how we know when a relationship is real. When someone else previously unconnected to us knows us in a way we never thought or believed possible.

I like that.

In bed that night, I looked over at Jake. He was so stable, babyish. He looked smaller. Stress and tension hide during sleep. He never grinds his teeth. His eyelids don't flutter. He usually sleeps so soundly. He looks like a different person when he sleeps.

During the day, when Jake's awake, there's always an underlying intensity, an energy that simmers. He has these little movements, twitches and ticks.

But isn't being alone closer to the truest version of ourselves, when we're not linked to another, not diluted by their presence and judgments? We form relationships with others, friends, family. That's fine. Those relationships don't bind the way love does. We can still have lovers, short-term. But only when alone can we focus on ourselves, know ourselves. How can we know ourselves without this solitude? And not just when we sleep.

It's probably not going to work out with Jake. I'm probably going to end it. What's unrealistic, I think, is the number of people who attempt an enduring, committed relationship, who believe it will work long-term. Jake isn't a bad guy. He's perfectly fine. Even considering the data that shows the majority of marriages don't last, people still think marriage is the normal human state. Most people want to get married. Is there anything else that people do in such huge numbers, with such a terrible success rate?

Jake once told me that he keeps a photograph of himself at his desk in his lab. He says it's the only photograph he keeps there. It's of him when he was five. He had curly blond hair and chubby cheeks. How did he ever have chubby cheeks? He told me he likes the photo because it's him, yet physically, he's completely different now from the child he sees in the photo. He doesn't just mean he looks different but that every cell captured in the image has died, been shed and replaced by new cells. In the present, he is literally a different person. Where's the consistency? How is he still aware of being that younger age if he's physically completely different? He would say something about all those proteins.

Our physical structures, like a relationship, change and repeat, tire and wilt, age and deplete. We get sick and better, or sick and worse. We don't know when, or how, or why. We just carry on.

Is it better to be paired up or alone?

Three nights ago, with Jake fully comatose, I waited for the light to start peeking through the blinds. On the nights I can't sleep, like that one, like so many recently, I wish I could just turn my mind off like a lamp. I wish I had a shutdown command like my computer. I hadn't looked at the clock in a while. I lay there, thinking, wishing I was asleep like everyone else.

"Almost there," says Jake. "We're five minutes away."

I sit up and stretch my arms over my head. I yawn. "Felt like a quick trip," I say. "Thanks for inviting me."