These objects look as if they could exist in three-dimensional space, but take a closer look . . .
Hollow Brick
Hollow Brick
Impossible Trident
Impossible Trident
The impossible trident is thought to have been created by D. H. Schuster, an American psychologist, who based it on an advertisement he saw in an aviation journal. It was first published in The American Journal of Psychology in 1964.
Garden Fork
Garden Fork
Devil's Magnet
Devil's Magnet
3 or 4 shelves?
3 or 4 shelves?
A figure by Oscar Reutersvärd
Tongue or Groove?
Tongue or Groove?
Technical Drawing
Technical Drawing?
Ambihelical Hexnut
Ambihelical Hexnut
Impossible Triangle and the Devils Pitchforks
Impossible Triangle and the Devils Pitchforks
Belvedere Crate
This figure appears in Belvedere by M. C. Escher
Impossible Triangle
The Impossible Triangle
A figure by mathematicians Lionel S. and Roger Penrose
Logs
It looks real enough, but look at the third log!
From Impossible Penetrations by Bruno Ernst ~ 1984
Penrose steps
The Penrose Staircase
A figure by the mathematician L. S. Penrose
This was used as the basis for M. C. Escher's Ascending and Descending
Joinery
Impossible joinery
Tribar
Tribar
Ring
Ring
Flat 8
Flat 8
Quadrature of the Wheel
Quadrature of the Wheel
See the pencil drawing by Sandro del Prete
Reutersvärd
Figures by Oscar Reutersvärd
Impossible Corner
Impossible Corner
Stool
Impossible Figures
Zenon Kulpa ~ ink and paper ~ 1980
Images of Illusion
Images of Illusion
From a screen print by Shigeo Fukuda ~ 1984
The Impossible Two - Bar
The Impossible Two - Bar
Bruno Ernst
Impossible Torus
Impossible Torus
Building an Impossible Arch
Building an impossible arch
Four Bar
Four Bar
Layered Blocks
From Layered Blocks
Oscar Reutersvärd
Two Arrows
From Two Arrows
Oscar Reutersvärd
Meander figure
Meander Figure
Elephant
How many legs does this elephant have ?
American cognitive scientist, Roger Newland Shepard (January 30, 1929 - May 30, 2022), first published this optical paradox in his 1990 book Mind Sights giving it the name "L'egs-istential Quandary."
Up or Down
Up or Down
This cartoon was drawn by Viuti with the title "Perspective - Men on Steps."
Viuti was, I believe, Argentinean and his real name was Roberto Lopez.
Folds
Folds
Has this piece of paper been folded or rolled?
© 1997, Gianni Sarcone, giannisarcone.com
Structural Constellations
"Structural Constellations" by Josef Albers - 1953 - 1958
This image was taken from "Optical Illusions and the Visual Arts" by Ronald G. Carraher and Jacqueline B. Thurston.
Reinhold Book Corporation, New York. 1966
Structural Constellations
"Structural Constellations" by Josef Albers - 1953 - 1958
This image was taken from "Optical Illusions and the Visual Arts" by Ronald G. Carraher and Jacqueline B. Thurston.
Reinhold Book Corporation, New York. 1966