Steven Pinker -- How the Mind Works - Hampshire High Italian ...

250 | HOW THE MIND WORKSillusion in a little parable. You are a designer who must build a stage setthat looks just like the right-hand diagram. You go to a workshop wherespecialists build scenery for dramatic productions. One is a lightingdesigner. Another is a painter. A third is a sheet-meta! worker. You showthem the picture and ask them to build a scene that looks like it. Ineffect, they have to do what the visual system does: given an image, figureout the arrangement of matter and lighting that could have brought itabout.There are many ways the specialists ean satisfy you. Each couldalmost do it alone. The painter could simply paint the arrangement ofparallelograms on a flat sheet of metal and ask the lighting designer toilluminate it with a single flood:The lighting designer could take a plain white sheet and set up nine customspotlights, each with a special mask and filter, aimed just right loproject nine parallelograms onto the sheet (six of the spotlights areshown here):The sheet-metal worker could bend some metal into special shapes thatwhen illuminated and viewed from just the right angle give rise to theimage: