Abstract
Illusions have been displayed in art for millennia but they were not addressed seriously by visual science until the mid-nineteenth century when Johann Joseph Oppel referred to the small spatial distortions as ‘geometrical optical illusions’. Many of the illusion figures described thereafter bear the names of those who illustrated them. Original forms of the illusions were shown together with illusory portrayals of those who described them. These included (in chronological sequence): Jan Evangelista Purkyně, Louis Albert Necker, Michel Eugène Chevreul, Adolf Fick, Johann Karl Friedrich Zöllner, Johann Christian Poggendorff, Karl Ewald Konstantin Hering, August Kundt, Joseph-Rémi-Léopold Delbæuf, Ernst Mach, Hermann Ludwig Ferdinand Helmholtz, Ludimar Hermann, Wilhelm von Bezold, Henri Beaunis, Franz Carl Müller-Lyer, Theodor Lipps, Armand Thiéry, Wilhelm Maximilian Wundt, Hugo Münsterberg, Friedrich Schumann, Hermann Ebbinghaus, Edward Bradford Titchener, Joseph Jastrow, James Fraser, Mario Ponzo, Edgar Rubin, Matthew Luckiesh, Friedrich Sander, Walter Ehrenstein, Adelbert Ames, Richard Gregory, Gaetano Kanizsa, Michael White, Roger Shepard, and Bernd Lingelbach.