Optical Illusions

Courtesy of reader Dave, check out this dazzling site filled with some really marvellous, and sometimes infantile, optical illusions. (Warning: Make sure you've taken your Dilantin® first.) On a semi-related note, allow me to recommend a wonderful book "Gödel, Escher, Bach: an Eternal Golden Braid" by Douglas Hofstadter that plumbs the interrelationship between form and content.

"These pages demonstrate visual phenomena, and 'optical' or 'visual illusions'. The latter is more appropriate, because most effects have their basis in the visual pathway, not in the optics of the eye."