An impossible object (also known as an impossible figure or an undecidable figure) is a type of optical illusion consisting of a two-dimensional figure which is instantly and subconsciously interpreted by the visual system as representing a projection of a three-dimensional object although it is not geometrically possible for such an object to exist (at least not in the form interpreted by the visual system).
In most cases the impossibility becomes apparent after viewing the figure for a few seconds. However, the initial impression of a 3D object remains even after it has been contradicted. There are also more subtle examples of impossible objects where the impossibility does not become apparent spontaneously and it is necessary to consciously examine the geometry of the implied object to determine that it is impossible.
Impossible objects are of interest to psychologists, mathematicians and artists without falling entirely into any one discipline.
Read more about Impossible Object: Notable Examples, History
Famous quotes containing the words impossible and/or object:
“It’s impossible for someone who is human to have all good things together, just as there is no single country able to provide all good things for itself.”
—Herodotus (c. 484–424 B.C.)
“If thinking is like perceiving, it must be either a process in which the soul is acted upon by what is capable of being thought, or a process different from but analogous to that. The thinking part of the soul must therefore be, while impassable, capable of receiving the form of an object; that is, must be potentially identical in character with its object without being the object. Mind must be related to what is thinkable, as sense is to what is sensible.”
—Aristotle (384–322 B.C.)