What did Einstein, Aristotle, and Salvador Dali have in common? All three of these three great minds knew how to use a little bit of sleep to inspire great ideas.

Take this appropriately absurd image for example: Salvador Dali, the master of surrealism, is slouching in his chair. In his right hand he holds a key. Beneath his hand is an upside-down plate. Once he falls into a deep sleep, his hand releases the key which clangs onto the plate and the painter awakes with a start, refreshed and ready to get weird.

For Dali, the time between the release of the key and the clank of the plate (coupled with the drifting off beforehand) is more than enough to throw yourself back at the canvas. As he writes in the 50 Secrets of Magic Craftsmanship:

The moment the key drops from your fingers, you may be sure that the noise of its fall on the upside-down plate will awaken you, and you may be equally sure that this fugitive moment when you had barely lost consciousness and during which you cannot be assured of having really slept is totally sufficient, inasmuch as not a second more is needed for your physical and psychic being to be revivified by just the necessary amount of repose.

Salvador Dali

This little lifehack of the micronap, which Dali said should not be longer than a quarter second, is also attributed to Einstein and Aristotle. Fascinatingly, sleep research is beginning to explicitly confirm what these three geniuses implicitly understood:

Sleep has multiple stages, and our bodies behave differently within each part of the process. This stage is called hypnagogia, which means “abducting into sleep.” As Arthur contributor Anthony Alvarado writes, it’s that “that liminal in-between state where you are just beginning to dream but are still conscious.”

The just beginning to dream part is important, as the halfway dream state as animated poets, inventors, and the like for ages. According to Alvarado, the list of hypnagogic creative types include:

Poet Samuel Taylor Coleridge, whose “Kubla Khan” is a record of half-dreamed reverie

Composer Ludwig van Beethoven, who grabbed ideas while napping in his carriage

Inventor Thomas Edison, who said that his mind was flooded with images when he was half-awake

Composer Richard Wagner, whose Ring Cycle has hypnagogic images

Philosopher John Dewey, who said people were most creative when they are “relaxed to the point of reverie.”

But the hypnagogic happenings are really only half the story: what’s brilliant about Dali’s drop-the-key method is that it allows the painter to leap back into his work. How so? Well, one of the dangers of an ill-executed nap is that you wake up with a deep sense of groginess, which research-types called sleep inertia. When we’re in a state of sleep intertia–which scientists have found comes after 20 minutes or more of sleep–we have to re-rouse ourselves to meet the remains of the day.