Nature Study in the Philadelphia Normal School ... when it is viewed as a white pattern on a black background this illusion disappears (or nearly so), and the black lines as well as the white ones seem parallel. Here’s a fun & simple optical illusion you can make – “The Jastrow illusion is an optical illusion discovered by the American psychologist Joseph Jastrow in 1889. Basically, the long-and-short of it (ha, we kill ourselves) has to do with how identical curved objects are placed in … and so on for the rest of the letters. The Jastrow illusion was first discovered in 1889, by… The Jastrow illusion is an optical illusion discovered by the American psychologist Joseph Jastrow in 1889. This optical illusion is known under different names: Ring-Segment illusion, Jastrow illusion, Wundt area illusion or Wundt-Jastrow illusion. The Jastrow illusion is an optical illusion attributed to the Polish-American psychologist Joseph Jastrow. The illusion works by messing with the perception. Jastrow Illusion. VIDEO: Jastrow Illusion in Action Take a look at this short and simple animated #gif showcasing the Jastrow illusion in action! The above illusion is called the Jastrow illusion found by psychologist, Joseph Jastrow. It looks like one of the pieces must be longer than the other, but both are the same size! The Mind's Eye by Joseph Jastrow. This is an example of the Jastrow Illusion, discovered in 1889 by psychologist Joseph Jastrow. In this illustration, the two figures are identical, although the lower one appears to be larger. The Jastrow Illusion is an optical illusion discovered by Joseph Jastrow in 1889. The rabbit-duck illusion is one of many illusions identified by Joseph Jastrow in 1899. In this image, the two figures are identical, although the bottom one appears to be larger.” [ via ] – Link.