Other Minds: The Octopus, the Sea, and the Deep Origins of Consciousness

by Peter Godfrey-Smith

Some features show a mixture of similarity and difference, convergence and divergence. We have hearts, and so do octopuses. But an octopus has three hearts, not one. Their hearts pump blood that is blue-green, using copper as the oxygen-carrying molecule instead of the iron which makes our blood red. Then, of course, there is the nervous system—large like ours, but built on a different design, with a different set of relationships between body and brain. The octopus is sometimes said to be a good illustration of the importance of a theoretical movement in psychology known as embodied cognition. These ideas were not developed to apply to octopuses, but to animals in general, including ourselves, and this view has also been influenced by robotics. One central idea is that our body itself, rather than our brain, is responsible for some of the “smartness” with which we handle the world. Our body’s own structure encodes some information about the environment and how we must deal with it, so not all this information needs to be stored in the brain.