Other Minds: The Octopus, the Sea, and the Deep Origins of Consciousness (alternatively subtitled The Octopus and the Evolution of Intelligent Life) is a science and philosophy book by Peter Godfrey-Smith, a professor of philosophy of science and an avid scuba diver. We recognize the intelligence of many animals among us, from our closest relatives in apes and monkeys, to the dogs and cats that live in our homes, and even some of the birds that live in our backyards. Yet there are creatures on this Earth, distantly related to us, that have anomalously developed surprising intelligence on their own. These are the cephalopods: squids, cuttlefish, and especially octopuses. This book is two-pronged, discussing just how consciousness and intelligence arrived on the evolutionary stage in the first place, and the ways in which it has emerged in cephalopods and what science has uncovered in studying their minds.

Though I knew very little going into this book, the intelligence of cephalopods has been a minor point of fascination for me. As Godfrey-Smith aptly puts it in the book itself, they’re likely the closest we will likely come to interacting with an alien intelligence. Despite other sources that I’ve read that lean into this otherworldliness, however, I was pleasantly surprised (if a little daunted) to learn how grounded in evolutionary biology this book is. It’s could be a lot to take in, especially considering how condensed it is, but I came away from it better informed about the broader strokes of the subject than I had expected from a book more specifically about octopuses.

He takes us all the way back to our earliest shared ancestor with cephalopods, a slug-like creature with limited vision that lived many millions of years before even the dinosaurs, to give context for just how long ago we split away from them in the evolutionary tree of life. The importance of this is in the fact that there are (relatively) far fewer degrees of separation between ourselves and other intelligent vertebrates, like other mammals or birds. Our bodies can be very different, but we share many anatomical similarities with them. Octopuses, squid, and cuttlefish on the other hand, have intelligence far greater than that of any other mollusks. With our last shared ancestor so seemingly brainless, cephalopod intelligence makes for a more distinctly separate emergence of consciousness.

Being a book of philosophy as well as science, a lot text is spent exploring the origins of consciousness itself and what denotes it in living things. He begins with how single celled organisms sense the world around them, building to the importance of the nervous system for consciousness in multicellular organisms. It could be dense reading material at times, but despite the fact I haven’t formally studied biology since high school, Godfrey-Smith writes about the topic in a way that was relatively easy to understand without feeling too dumbed-down. The way he describes just how complex an octopus’s nervous system is and how that affects the way that it thinks was especially fascinating.

What made for easier reading, woven throughout the examination of consciousness itself, were accounts of actual octopus behaviours observed in laboratories and in the wild. These were absolutely charming sections of the book, showcasing the cleverness and trickery these animals are surprisingly capable of. This wasn’t at the expense of the science and philosophy, however, as he still used these moments to more deeply explore scientific methods, explain cephalopod anatomy and physiology, and consider the greater implications of what they can do and how they behave.

He often writes about his experiences in the field, especially his many trips to “Octopolis,” an anomalous collection of many individual octopuses and their dens in a centralized area off the coast of Australia. Chapters spent discussing this place were definitely the main attraction of this book for me and I was always eager to learn more about this strange place. It’s uncanny, because octopuses are not social creatures, yet a settlement upon a bed of scallop shells seems to have developed by chance, putting these intelligent animals in an environment where they can thrive, yet are constantly made to interact by proximity.

His descriptions of the animals’ behaviours and interactions with him were wonderfully vivid, making it easy to imagine myself there. He often uses these observations to puzzle over the seemingly contradictory attributes of the octopuses of Octopolis, as well as cuttlefish. For example, they (especially cuttlefish) can and often do change the colour of their bodies in elaborate ways that do not benefit camouflage, yet they are all colour-blind. If these displays are not for defense or communication, what are they for? He offers well-reasoned, detailed explanations from his research, yet I felt questions such as these were left open enough for the reader to continue wondering about what more they could mean, long after the book has been read.

Final Thoughts

Other Minds is almost exactly what I want from scientific nonfiction. The writing made for enjoyable reading, without scrimping on the more challenging information that really got me learning about a subject I was excited to know more about. It has an extensive note section for each chapter at the back too, for those who wish to dive deeper into further material. My only real gripe with the book is that once you reach the “Notes” section it’s only been about 200 pages, and I would have happily read more.

My Rating: 4.5 out of 5