Peter Godfrey-Smith’s Other Minds: The Octopus, the Sea, and the Deep Origins of Consciousness is one of the most ambitious 200-page books I’ve ever encountered. It’s fascinating, eye-opening, and a little frustrating. Godfrey-Smith is a philosopher (please don’t stop reading now, he’s not that kind of philosopher) with a strong background in science who’s given us a book that is about the evolution of consciousness, the various theories of how to determine whether or not a creature in fact has consciousness, and how all of this applies to the octopus. The frustrating part is that there’s no way to cover all of that ground sufficiently to satisfy my curiosity in just 200 pages.
The evolution of nervous systems and the theories as to how, where, and why consciousness arose are the meat and bones of the book. We’re reasonably certain now that cetaceans and birds exhibit behavior that indicates consciousness, but in terms of evolution, they’re all pretty close to where we are on the tree. All of the chordate nervous systems evolved in much the same way, so as unknowable as crows and whales are to us, they not put together that differently than we are.
That brings us to the octopus. Their branch of the evolutionary tree of life diverged from us quite some time ago. Their nervous systems, which are incredibly extensive, are nothing like our own. Nonetheless, the octopus behaves in ways that indicate consciousness. When you’re face to face with an octopus, you’re as close to encountering an alien mind as you’re ever likely to come.
The cuttlefish also gets a good deal of time in the book. They’re a relative of the octopus, and their behavior is perhaps less indicative of consciousness, but there’s enough there to leave the question open. And here’s the weird thing: The cuttlefish nervous system evolved completely separately from that of the octopus. So these unusual, extensive nervous systems evolved separately three times: In chordates, in the octopus, and in the cuttlefish.
Would I recommend the book? Oh hell yes I would. If you’re remotely interested in any of the subjects touched on above, you’ll probably love it. Just understand that it will likely leave you feeling unsatisfied in that you’ll want to know more about pretty much every subject Godfrey-Smith touches on.
Also, if you’re anything like me, you won’t feel so good about eating octopus.
-RK