On Being an Octopus


Peter Godfrey-Smith in Boston Review:

If octopuses did not exist, it would be necessary to invent them. I don’t know if we could manage this, so it’s as well that we don’t have to. As we explore the relations between mind, body, evolution, and experience, nothing stretches our thinking the way an octopus does.

In a famous 1974 paper, the philosopher Thomas Nagel asked: What is it like to be a bat? He asked this in part to challenge materialism, the view that everything that goes on in our universe comprises physical processes and nothing more. A materialist view of the mind, Nagel said, cannot even begin to give an explanation of the subjective side of our mental lives, an account of what it feels like to have thoughts and experiences. Nagel chose bats as his example because they are not so simple that we doubt they have experiences at all, but they are, he said, “a fundamentally alien form of life.”

Bats certainly live lives different from our own, but evolutionarily speaking they are our close cousins, fellow mammals with nervous systems built on a similar plan. If we want to think about something more truly alien, the octopus is ideal. Octopuses are distant from us in evolutionary terms, have a nervous system of very different design, and bodies with no bones and little fixed shape at all. What is it like to be an octopus? The question is intrinsically interesting and, beyond that, provides a good way to chip away at the problem Nagel raised for a materialist understanding of the mind.