Kathryn Harrison spoke to me by phone from her home in Brooklyn.

Kathryn Harrison: I don’t know when I first encountered Joseph Brodsky’s poem “On Love,” but I know what reawakened my interest in it. I was in Boston looking at the collection of Rothkos at Harvard, and a line from the poem popped into my head—as if the Rothkos had summoned it.

It’s a poem about a man who has dreamt about his dead partner. The possibilities that were destroyed by losing her are restored in the dream: the idea of their making love, and having children, and being in each other’s company. It ends by underscoring the commitment that extends beyond mortal life—in a realm that is not conscious, not present here, not material, not cerebral. You might call it the realm of the mystical, or the ineffable. Whatever you want to call it, it’s a realm I believe in.

Throughout the poem, Brodsky sets up a contrast between light and darkness. With the lights out, memories of the dream-woman consume the narrator—so much so that she seems to become real. When he flicks the light on, though, she vanishes:

And with the bulb turned on

I knew that I was leaving you alone

there, in darkness, in the dream, where calmly

you waited till I might return ...

Many human transactions take place in this realm of darkness. On unconscious planes, through dreams—even, on some level, in people’s ability to communicate without words. By darkness, I don’t mean black, as in lacking light. I mean dark: the aspect of life that is not accessible through our conscious processes of analysis.

The poem’s essence is in this line:

For darkness restores what the light cannot repair.

I think Brodsky means that light can “repair” things in the material world, but that there are limitations of that kind of fixing. Medicine, for instance, can heal in the light. But if the spirit isn’t well, there is no life. And there is no way to restore what’s lost, sometimes, other than through dreams and imagination.

I don’t think I’m saying something sad when I say that. There’s huge redemption in the fact that there is a world that is dark, or opaque, to conscious life. The realm of darkness that heals and restores, and allows memory to bind up, provides the present with a kind of solace that is almost holy. The line is about the holy and generative properties that exist within us. And so, I think the line is about God. A realm that God inhabits.

We could probably say that about a Rothko, too.

The line also defines writing, at least writing the way I experience it. For me, writing is a process that demands cerebral effort, but it’s also one informed by the unconscious. My work is directed by the needs of my unconscious. And through that dark, opaque process, I can restore what might otherwise be lost. In a novel, I can restore lost voices—usually a woman’s—and give words back to the silenced. Or in memoir—The Kiss restored my voice, broke a silence imposed on me.