The feather you see above looks like it’s moving in slow motion. It’s not. In fact, it’s moving rather quickly. But thanks to some clever lighting, and the limits of human perception, it seems to sway at an impossibly languid tempo.

Do you grok it? It’s okay if you don’t. “It’s a very startling thing when you see something that’s physically in front of you but doesn’t align with your mental model of reality,” says designer Jeff Lieberman, who specializes in this kind of visual trickery. As the of host of the Discovery Show Time Warp, he used a high-speed camera to deconstruct the physics of things like gunshots, ballet dancers, and explosions. At Plebian Design, his design studio, Lieberman and his team build room-sized installations that mess with a viewer’s sense of perspective.

He calls his latest illusion “Slow Dance.” On Kickstarter (where, as of this posting, it has nearly quintupled its fundraising goal), he describes it as “a frame that slows down time.” But it does no such thing.

In fact, Slow Dance relies on a surprisingly simple, if imperceptible, trick. “Once you tell someone how it works, they can never un-know it,” Lieberman says. He’d rather you puzzle it out on your own, but if you’re really persistent, he’ll insist that you devote one solid minute to figuring it out.

So go ahead. Take your minute. Give up?

Jeff Lieberman

The secret to Slow Dance is a careful timing of light and motion. LEDs, hidden in the edges of the wooden frame, strobe at a frequency between 79 and 81 blinks per second—so fast that your eyes don’t even register that the lights are flickering. Meanwhile, an electromagnetic motor at the base of the frame vibrates the object in its clutches—a feather, a leaf, a flower—at a frequency of 80 Hz.

The blinking lights illuminate the vibrating object as it flails about, but at a rate that is just out of phase with the object’s movement. If the frequencies were perfectly synced, the object would appear not to move at all. Instead, the lights briefly illuminate the object at various points along its path of movement. Each illumination event is like a snapshot in time—but these snapshots occur at such a high frequency that your brain perceives them as an object in motion, rather than discrete images. The effect hinges on a phenomenon called persistence of vision. Even if you’ve never heard it called by name, you’re intimately familiar with it; everything from movies to flip books depend on it to create the illusion of continuous motion.

Like many great illusions, knowing how Slow Dance works does little to dilute its impact. Looking at an object through Lieberman’s frame feels a bit like peering in on a hidden world. Suddenly you can see the bend of a feather’s barbs. Plants feel more alive because you can see them move. As for Lieberman, he hopes his creation will help people slow down themselves, if only for a split second. “As adults we get complacent about mystery,” he says. “This really engages someone in a state of wonder.”