
It’s been one heck of a year but we’re on the house stretch. Now, let’s celebrate by watching something very strange that seems to make no sense.
What we’ve here is the winner of this year’s Best Illusion of the Year Contest 2020 and it’s indeed a worthy mind boggler, taking one among the best known traditional 2D optical illusions & realizing it perplexingly in three-dimensional space.
Designed by mischievous mathematician Kokichi Sugihara, a celebrated Japanese illusionist & repeat winner whose work we’ve featured more than once on the site, this is often called the 3D Schröder Staircase.
The classic Schröder Staircase published in 1858 by German scientist Heinrich G. F. Schröder would later evolve into other forms in the work of Dutch artist, M. C. Escher, but the striking simplicity of the original remains a stunner.
In the illustration, what initially appears to be an unambiguous depiction of one staircase seen from above seems to be two staircases.
If you cannot visualize it, simply turning Schröder’s Staircase upside-down tends to form the alternative perspective visible, but maybe just for a fleeting second, before your mind undergoes psychological phenomenon of the Gestalt Shift, where your perception switches back to its earlier interpretation.
In his new twist on this already-twisted topic, Sugihara has now reverse engineered the same 2D staircase illusion into a 3D form, devising a cardboard cut-out that does the precise same trick when viewed from a particular perspective, even though the actual physical shape of what you are looking at is nothing-like what it seems.
“The present 3D object also has 2 interpretations, both of which are staircases and the interpretations switch from one to the another once we rotate the object by 180 degrees around the vertical axis,” Sugihara says.
But just because that is what it’s look like doesn’t mean that’s what it is.
On his website, Sugihara teases how illusion is really constructed, going as far to provide a free ‘construction kit‘ diagram for the impossible-steps, just in case you feel like making a set to keep at home.
At the heart of illusion is a simple trick: the stairs might appear as stairs, but they’re actually a flat surface, making clever use of angles & shading to fool your brain.
To make the work of visual perception easier, our brains make convenient assumptions wherever they will. Dark tones mean shadows, hinting at depth – converging lines are usually a measure of distance. Throw them together & your lazy brain will do its best to seek out a familiar story to fit the shapes. Sure, it’s wrong, but usually these shapes do in fact make up staircases.
“This object is an example-of my experimental material to investigate the behaviour of the brains which are apt to misperceive 2D pictures as 3D objects, once they are embedded in real 3D structures,” Sugihara explains, noting that the addition of real 3D side walls & support columns fills-out the bewitching illusion.
“As the result, we perceive new ambiguity which is different from that of the original Schröder Staircase.”
In addition to turning the 3D Schröder Staircase around (the 3D equivalent of turning the 2D illustration upside-down), careful positioning with a mirror reveals something uncanny: both perspectives seen-simultaneously and there is not a thing the Gestalt Shift can do about it.
Marvellous. Congratulations, Kokichi Sugihara!
For more mind blowing illusions from this year’s competition, all of the finalists are often seen at the Best Illusion of the Year Contest website.