I closed my eyes and tried to imagine myself hollow. At first, I could only picture myself filled with blackness. Black sand, heavy and glittering. But after a while, I thought I could scrape it away, replace the scrim of colored-in, covered-up organs with real nothingness, negative space. I imagined air inside, pushing against the skin of my stomach, and then the opposite of air, pulling.

When Luke spoke again, I nearly jumped. “Now visualize a channel,” he said. “The channel begins between your legs and goes up through the top of your skull. Take all of the energy from your body and make it into a ball of heat. The ball of heat will start at the bottom, at your sacrum, but then you can move it up, toward your crown, where there’s a hum. Don’t let it out.”

I pictured a small white-hot ball with a little red tail, like a comet. I let it rest in the bowl of my pelvis. I thought I could hear the noise it made, a hot whir like a gas stove. I held it down between my legs until I couldn’t hold it there any longer, because I didn’t know what would happen if I did, and then I let it go, and it jumped up into the channel I had made, which was blue, and filled it with red light. The light climbed up through my body. I wanted it to go slowly, but it wanted to go fast, and I could barely control it.

“Breathe deeply into the space four inches below your navel, and focus on the ball of heat, let it rise, and then let it fall. Hold the heat in your mind and the breath in your body.”

I had to keep the ball from escaping through my mouth by gritting my teeth. Rebuffed, it found its way into my head, and for a moment I thought my skull would explode. Then I remembered what I was meant to do next, and I started pushing it down, back toward my pubic bone, which seemed cold, and so far away, as though my body stretched forever between the two.

“Don’t let it out,” Luke said again, or maybe it was only an echo.

My eyes were closed, and I could see the ball of light, but I also thought I could see Luke, who had begun to speak in a language I didn’t know, or in a language I knew but couldn’t understand. I opened my eyes slightly and saw only darkness. It wasn’t frightening; it was inviting, a bedroom darkness. I closed them again and the world looked the same. Open, closed. If we’re inventing our reality, why not do it in the dark? The light inside of me was blocking out everything else; the pressure was building, blinding.

“Okay,” I heard him say at last. “Let it go, and exhale through every pore in your body.”