Now we learn that an octopus can see with its skin. The skin is not only affected by light—something true of quite a few animals—but it responds by changing its own delicate, pixel-like color-controlling machinery. What could it be like to see with your skin? There could be no focusing of an image. Only general changes and washes of light could be detected. We don’t yet know whether the skin’s sensing is communicated to the brain, or whether the information remains local. Both possibilities stretch the imagination.
