What would it be like to see with your skin?
In the octopus's case there is a conductor, the central brain. But the players it conducts [the animal's limbs] are jazz players, inclined to improvisation, who will accept only so much direction. Or perhaps they are players who receive only rough, general instructions from the conductor, who trusts them to play something that works. [...]
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. If the skin's sensing is carried to the brain, then the animal's visual sensitivity would extend in all directions, beyond where the eyes can reach. If the skin's sensing does not reach the brain, then each arm might see for itself, and keep what it sees to itself.