“Clearly dreams do something for us,” writes Michael W. Clune. “If not, why would evolution have endowed us with the capacity?” In this essay, Clune explores the fascinating world of dream engineering via a device called the Dormio, which enables a person to shape the images that appear during hypnagogia, the transitional stage between wakefulness and sleep.

After a few days of this, I found I was developing a sense, even a taste, for hypnagogia. Now, when I go to sleep, I watch for it. It’s the moment when thoughts take on a life of their own. Or more accurately, when they resume the life they’ve always led when I’m not there.

Cheri has been an editor at Longreads since 2014. She's currently based in the San Francisco Bay Area.