Impossible object

An impossible object (also known as an impossible figure or an undecidable figure) is a type of optical illusion that consists of a two-dimensional figure which is instantly and naturally understood as representing a projection of a three-dimensional object but cannot exist as a solid object. Impossible objects are of interest to psychologists, mathematicians and artists without falling entirely into any one discipline.

^ Bruno Ernst (Hans de Rijk) (2003). "Selection is Distortion". In Schattschneider, D.; Emmer, M. (eds.). M. C. Escher's Legacy: A Centennial Celebration. Springer. pp. 5–16. ISBN 978-3-540-28849-7.
^ Barrow, John D (1999). Impossibility: The Limits of Science and the Science of Limits. Oxford University Press. p. 14. ISBN 9780195130829.

[1] Bruno Ernst (Hans de Rijk) (2003). "Selection is Distortion". In Schattschneider, D.; Emmer, M. (eds.). M. C. Escher's Legacy: A Centennial Celebration. Springer. pp. 5–16. ISBN 978-3-540-28849-7.

[2] Barrow, John D (1999). Impossibility: The Limits of Science and the Science of Limits. Oxford University Press. p. 14. ISBN 9780195130829.

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