In our culture, we're taught to fear the darkness. It's built into our myths and our popular culture. Do you ever get frightened on a retreat?

No, but I do know people who have been scared. I've led a lot of these retreats, and my sense is that generally that doesn't happen. What happens when you are very relaxed is that you don't tend to get into those kinds of reactive fears.
Actually, one of the main concerns that people have is that they will be incredibly bored. That doesn't tend to happen either, and I think it's because a lot of boredom is about a desire for stimulation.
What do you mean?
It's the momentum of our brains wanting to think about things and the constant mental chatter that makes us look for ways to keep ourselves awake by being interested in something. When you relax, you don't need that stimulation. Being in the dark is sort of like being in a very safe womb.

How did you happen to start doing dark retreats?
There's a Tibetan lama named Lon Gil Rimpoche that I know quite well. He gave a series of talks here in the Boston area, and he introduced dark retreats as part of the teachings. Then I created this dark retreat space to do it myself.
You grew up in San Francisco. Were you raised with a particular religion?
My family was Jewish by background, but they were sort of non-observing, although my grandfather was a practicing Orthodox Jew. By the time I was an adolescent, I had read a lot on Buddhism. And when I began to feel spiritual impulses at that age, that's where I turned.
What's the main thing people can learn from a dark retreat?
I think the main thing you learn is what it means to be profoundly relaxed. We often think of relaxation as going unconscious, zoning out in some way. And this is a way to be relaxed and completely alert, with a clarity of presence.
The other thing is that you discover very quickly how your mind works because whatever thoughts arise in that state are so clearly something generated by your own habits of mind. So it becomes a way to see those patterns and experience the real possibility of moving beyond them by wholeheartedly participating in what's going on in our lives.