In 1688 Irish philosopher William Molyneux wrote to his colleague John Locke with a puzzle that continues to draw the interest of philosophers and scientists to this day. The idea was simple: Would a person born blind, who has learned to distinguish objects by touch, be able to recognize them purely by sight if he or she regained the ability to see?
Image: Bee recognizes a sphere by sight even though it had previously only been trained to detect it by touch. Credit: Lars Chittka
