Metazoos: La evolución de la vida y el nacimiento de la consciencia

by Peter Godfrey-Smith

Combining science, philosophy, and his own observations gleaned from "watery hours" spent scuba diving, Godfrey-Smith (history, philosophy of science, Univ. of Sydney; Theory and Reality) examines the origins of animal consciousness. In his work, Other Minds, the author focused on octopuses; here, the book's "tentacular form" shows him considering several animal groups as he investigates the puzzle of how subjective awareness came to exist. This is no dry, academic treatise; Godfrey-Smith takes care to keep the work accessible by summarizing key points, explaining the work of relevant scientists and philosophers, and punctuating the text with memorable facts. The book is enlivened by the wit and affection with which the author often regards his subjects of study. He writes, for example, of the arthropod way of evolving ("when in doubt, add some legs") or the mantis shrimp's odd appearance ("a head festooned with golf clubs and party lights"). An astonishing range of creatures are considered and a fascinating argument advanced about how evolutionary innovations can give rise to animal minds.

Genres: Science, Nonfiction, Philosophy, Biology, Nature, Psychology, Animals

417 pages, Kindle Edition

First published November 1, 2020

About the author

I am currently Distinguished Professor of Philosophy at the Graduate Center, CUNY (City University of New York), and Professor of History and Philosophy of Science (half-time) at the University of Sydney.

I grew up in Sydney, Australia. My undergraduate degree is from the University of Sydney, and I have a PhD in philosophy from UC San Diego. I taught at Stanford University between 1991 and 2003, and then combined a half-time post at the Australian National University and a visiting position at Harvard for a few years. I moved to Harvard full-time and was Professor there from 2006 to 2011, before coming to the CUNY Graduate Center. I took up a half-time position in the HPS program at the University of Sydney in 2015.

My main research interests are in the philosophy of biology and the philosophy of mind. I also work on pragmatism (especially John Dewey), general philosophy of science, and some parts of metaphysics and epistemology. I’ve written four books, Complexity and the Function of Mind in Nature (Cambridge, 1996), Theory and Reality: An Introduction to the Philosophy of Science (Chicago, 2003), Darwinian Populations and Natural Selection (Oxford, 2009), which won the 2010 Lakatos Award, and Philosophy of Biology, released in 2014 by Princeton.

My photos and videos have appeared in the New York Times, National Geographic, Boston Globe, Boston Review, and elsewhere.

Reviews

[Petra X · Rating 5 out of 5]

Small update I was reading other reviews, and those who don't like philosophy mixed in with their science don't like it so much. But thinking about consciousness - it's one of those things we know for 100% certain exists but no one knows where or can define exactly what it is and which creature has it and which definitely don't. So how can you leave out philosophy?
____________________

I wish I hadn't read this book. The book is mind-expanding, paradigm-shifting as much from the philosophy as the scientific observations. It's an expanded conventional view of evolution but adds in philosophy and somehow poetry, there is a poetry in the author's descriptions of the animals, mostly marine ones, he interacts with. It was startling to read of him stroking a cleaner shrimp and it turning round and looking at him. Then later in the book, the test that proves the animal has selfhood, a mark on the face, a mirror, and the shrimp touched the mark on it's face from seeing its reflection. It's a hard thought, what does a shrimp think of itself and of the world it knows? It must think, there is no instinct that could account for its mirror action. This book is not just science, it's a very beautiful book. I wish I hadn't read it yet, I wish I was going to just start it for the first time again.

The book explores consciousness, selfhood, and when decision-making at the basic, instinctive, chemical level such as in very simple animals with few cells, when it becomes 'mind', where the mind is, how many minds could we have - people with split brains (from operations to help control epilepsy), seem sometimes to have two minds.

There was much to think on and now I'm reading Tales from the Ant World, I'm thinking on octopuses both in this book and the author's Other Minds: The Octopus, the Sea, and the Deep Origins of Consciousness and thinking how octopuses have in a completely different evolutionary branch developed eyes and the ability to manipulate objects with curiousity like people, not like other molluscs and fish and how ants are a parallel world to people, and wondering about consciousness, mind and especially with ants, selfhood.

An amazing 10 star read for me.
__________

Everything necessary to produce mammals, primates and us, had evolved in the sea. A flexible body, a capacity for manipulation and a centralised brain. But no one sea creature evolved all of these together. "This combination arose independently in two big branches, in early dinosaurs and mammals. It was transformed again in the dinosaurs who survived - birds - and came to a particular fruition in primates, like us." Is that beautiful writing? Science and writing at their best.

I love this book. I don't want it to end so I am rationing it!
___________________

You know the mirror test? Where the researcher puts a blob of something on the face of an animal and they look in the mirror and if they see it they touch it on their own face? Very few mammals and birds pass this - toddlers only 'get it' around 20 months, However, cleaner shrimps pass the test! They have superb vision, more really than anything we can imagine, but it is consciousness that tells you that it is 'you' that is in the mirror and not another shrimp, baby or cat. Cats, with their obvious feelings of superiority and disdain for human emotions when they feel like it, are very hard test subjects. They fail the attachment test too - where a child or puppy runs to the mother who has returned to a room where there is only a stranger now - but I think that's because cats expect the mother to run to them.

This book is brilliant and mind expanding, although I struggled quite a lot with the physics of electrical impulses in single-celled organisms. Truthfully, I struggled with all the physics. However, to be able to write about evolution from an organic and philosophical way as well as scientific, made the struggle worth while.

I have learned something new that has changed my perception of the world. We tend to think of evolution as a tree and things like cockroaches and lizards as lower down. No, says the author, we are all on the same plane, we are all at the very top level of our own development.

[Elentarri · Rating 3 out of 5]

In an attempt to examine the origins of animal consciousness, Peter Godfrey-Smith has written what is essentially a semi-coherent, superficial mish-mash of science, philosophy and memoir.  The author starts off with sea sponges and ends up with vertebrates, writing vaguely about their nervous systems and how they sense/interact with their environment.  The "animal facts" are very interesting.  So are the vignettes about the author's experiences with animals when diving.  However, Godfrey-Smith is not very good at explaining why any of these "animal facts" and experiences are relevant to his thesis/hypothesis, or how it fits into the bigger picture.  An intelligent reader that is paying attention can figure it out, but the book isn't particularly well written, the topics aren't covered deeply enough to be really useful, and Godfrey-Smith tends to ramble too much.  Maybe a different organizational structure would have helped?  Covering animals as they evolved does tend to lead to rather a lot of repetition.  This book lacked substance and was therefore, disappointing.  If the Peter Godfrey-Smith ever wrote a diving memoir with interesting "animal facts" thrown in, I would read that (he is good at the memoir stuff), but I would have to think really hard about another science-philosophy-memoir mishmash.

[D · Rating 3 out of 5]

A bit superficial and too long. I learned some interesting concepts related to consciousness: experience, subjectivity, agency, sentient etc. And how these applied to various animal species. But no detail, e.g. a more detailed explanation of the role of genetics in evolution. There certainly were many entertaining descriptions of amazing types of animals. But, again, rather superficial. In the end I discovered that the author is a philosopher, that may explain his focus. My mistake.

[Peter Tillman]

I was dubious about this one, since I didn't care for his earlier Octopus book. But I was low on stuff to read, saw it at the library, and took it home. I didn't get far. Not rated, and definitely not recommended! But lots of others liked it . . .

Here's the review that lead me to try this, by an actual biologist, who's been a pretty reliable reviewer for me: https://inquisitivebiologist.com/2020...
Excerpt:
"Compared to Other Minds, Metazoa dives deeper into neurological and philosophical topics: qualia, pain, emotions, types of memory, and others. It is, altogether, a more challenging book, though in a stimulating way. I am not sure it will have the same wide appeal as Other Minds, but for those readers interested in joining him on his quest to understand the evolution of mind, consciousness, and subjective experience, Godfrey-Smith delivers in spades."

Here's an excerpt from the book, with photos and a short video from "Octopolis": https://www.atlasobscura.com/articles...

Earlier stuff:
WSJ review: https://www.wsj.com/articles/metazoa-...
(Paywalled. As always, I'm happy to email a copy to non-subscribers.) I was pretty enthused on reading this review, until I recalled that I was lukewarm on his octopus book, finding it too heavy on philosophy. Maybe this one has more biology and less philosophy? Um. The author is a professional philosopher -- & I'm generally kinda allergic to philosophic maunderings.

[Carl Safina · Rating 4 out of 5]

One of my newly favorite authors and thinkers returns again to consider what consciousness is and what creates the ability of an entity to experience sensations. We know that much of our brain and body does things "in the dark," directing and carrying out high and complex functions without our being aware of them and with no decision-making ability. We also know that part of our brain and the brains of many other species functions as what we can call a "mind," capable of creating experienced sensations through input from sense organs, capable of imagining, of remembering, of deciding. Here in Metazoa we are talking about how this happens. So there is much illuminating science. But no one is quite sure how it happens, and the competing and conflicting ideas--along with the author's encounters with undersea animals and the abundant evidence of their conscious perception and sentience--makes this book very, very interesting.

Some sections verged a bit on the academic (I say this as an academician, as is the author). But so what. Godfrey-Smith takes us for a ride on the frontier of knowledge and informed speculation. Very worth the time and the reading.

[Mircea Petcu · Rating 5 out of 5]

Simțurile și acțiunile nu au fost inventate de animale. Organismele unicelulare pot detecta atingeri, substanțe chimice, lumina și chiar câmpul magnetic al Pământului. Și se pot deplasa țintit grație citoscheletului.

La animale, organisme pluricelulare, simțurile și acțiunile sunt mult mai complexe. Un pas cheie în coordonarea acțiunii animalelor a fost apariția sistemului nervos, probabil în apele Ediacaranului (acum 540-575 milioane de ani). Multe dintre inovații au apărut la organismele marine. Viața însăși a apărut în apele Oceanului Planetar. Cartea tratează în principal animalele marine: bureți, corali, creveți, caracatițe și pești oceanici.

Spre deosebire de ”Celelalte minți”, autorul a dedicat puține pagini filosofiei (Peter Godfrey-Smith este filosof). Capitolul cinci și ultimul capitol sunt de filosofie a minții.

[B. Rule · Rating 3 out of 5]

Some books have an urgency and necessity about them. This is not that kind of book. While there's nothing egregiously wrong about Godfrey-Smith's thinking, neither is there anything essential here that justifies the existence of the book. Godfrey-Smith is ostensibly building up a picture of how consciousness arose from the gradual accretion of components in animal minds, which he does primarily by haphazardly describing a few species he saw while futzing around in his hobby as a diver. You get descriptions of animals like corals, banded shrimp, cephalopods, and nudibranchs, and you can feel his desire to knit them into a story about the emergence of creatures as experiential beings.

The spirit is willing, but the flesh is weak. Lack of organization, weird strawman intuitions, and inert follow-through result in a flabby and largely unsatisfying effort. Godfrey-Smith floats along like a jellyfish in the current, half-heartedly nibbling little bits of philosophy and neuroscience but never absorbing a full meal. There are some interesting implications of his gradualist view, including challenges to the essential unity of conscious experience, but he doesn't do enough to draw them out. Instead, I got the sense that he mostly likes writing natural history, but his publisher wouldn't accept a simple dive diary after his last book (more successfully) married philosophy of mind with his reef explorations. Without the singular focus on the octopus to hone his arguments, this one dissipates like an inky cloud, vague and frankly a little obfuscatory.

Further, his goals are pretty modest. The opening pages led me to expect a robust challenge to the framing of the hard problem of consciousness, but his answer is a pretty anemic "qualia are just what it is to be this kind of creature." The only distinction he puts forward with any assurance is that sentience is not a separate product of a brain's operations. Okay, sure, but that doesn't tell you a lot, does it?

He also lost me by repeatedly talking about how we all assume insects and other animals farther out on the tree of life are mere robots without interiority. I guess he's fighting an army of Descarteses. However, I was just scratching my head because that's certainly not my intuition. We may not credit their subjectivities are worthy of protection, but I don't assume that the flies I swat have none.

Despite the overall failure of the project, I didn't dislike the book. Godfrey-Smith is good at describing animal behaviors (usually through significant anthropomorphism), and his self-effacing manner holds some charm. His gentle chiding to recognize mindedness in a wider circle of other creatures has welcome ethical implications. The final chapter has the obligatory pious protestations that minds are not substrate-independent that seemingly all pop-sci books must have these days, thus shutting the door of consciousness behind us for various transhumanist utopias of strong AI and mind-uploading. If you go into this book with your expectations very low (no, lower than that), you won't have a terrible time. But don't expect anything as good as his previous book, flawed though it was, nor anything close to the heights reached by the best books on neuroscience out there. 2.5/5 stars, although I'll round up since its greatest crime is mere mediocrity.

[Richard · Rating 3 out of 5]

“Metazoa”? One of the main branches of the tree of life: there are all the single-celled entities, of various kinds, then the plants, the fungi, the animals. Metazoa are the animals.
    More specifically though, this book, “…is in some ways about the evolution of subjectivity—what subjectivity is and how it came to be…”; it’s about, “…the evolution of the mind and how it fits into the world…”; it states that, “Given some arrangements of things that are not themselves mental, a mind comes to exist… That coming into being is the topic of the book.”
    And, well, yes it is…sort of. It does begin brilliantly, the first four chapters exploring themes from back before animals existed: bridging the so-called “gap” between the non-living and the living; there’s also a good attempt at expressing the unimaginable, the truly mind-bending, nano-scale of the events being described; then living things considered as electrical systems; then symbiosis and meta-symbiosis as one of the main ways we get from bacteria to animal cells. A key idea is the intimate (and sometimes surprising) relationship between sensing and action, between not only monitoring your surroundings but also moving about in them—neither of which were invented by animals, but both of which shift up a gear when animals do finally arrive on the scene. In particular, when you go from not moving (like sponges say) to moving about (jellyfish, worms and so on) this has huge advantages, but doesn’t come for free; you pay for it, and one of those costs is that suddenly the world is a more potentially confusing place. An animal has to infallibly distinguish between those changes which really are happening all around it from those apparent ones caused by its own moving about. “If an animal does not do something like this, its own motions will confound its attempt to understand what is going on. If an animal does do this, it is now sensing the world in a way that tracks the divide between the animal itself and everything else.” In other words, this combination of sensing and action leads to a demarcation, a separation, between me (in here) and everything else (out there). Already, this early in the book (and in the evolution of animals themselves) you can see where this idea might be leading us.
    Unfortunately, though, that’s it. By comparison, the remaining two-thirds of Metazoa is a mess—an interesting mess, true, in places a fascinating mess. There are some good facts (for instance, although I already knew that there are species of fish who are warm-blooded like birds and mammals, I certainly didn’t know that some of those are sharks, including the famous great white from Jaws); and some good lines (two octopuses fighting is described as “like a giant pillow-fight, between pillows”). But from around page 100 on we’re just circling round the subject of animal consciousness—warm-bloodedness, brain-waves, memory, you name it—without ever getting at it.
    Those first four chapters are certainly worth reading if you are at all interested in this sort of thing; the rest, though, left me wondering why the author wrote it (he’s a philosopher after all, not a biologist). Just a hunch, but maybe he’s found he enjoys writing as much as he does scuba diving.

[Janne Sinkkonen · Rating 5 out of 5]

(Listened, not read, which may affect my impressions.)

I have read both "Philosophy of Biology" and "Other Minds" from the author, and like his style, which is non-combative, often searching for a middle way or a synthesis. This book is a bit like Other Minds in that it mixes (often) tranquil diving scenes with more conceptual science and philosophy, in this case evolutionary history of animals, especially their movement, senses and associated implications to cognitive organisation. A carrying theme, although mostly discussed at the beginning and at the end, is philosophy of mind.

I think the discussion of animal evolution and animal minds was excellent, and there is not much to disagree.

On philosophy of mind, he describes himself as a materialist, material monist, and gradualist. This is all ok, for me personally and as a good background for most of the more concrete issues discussed. What bothers me a little bit, but just a little because it is a kind of side track in this book, is the treatment of the hard problem (of consciousness).

Notably, he is critical of panpsychism, but says something like "this is what it feels to *be* the matter, instead of looking at it outside as an observer". But this is exactly what a panpsychist, Philip Goff says! I'd definitely classify the view presented in Metazoa as a panpsychist, the kind of variety which associates the potential of consciousness for all matter but requires nervous systems for it to appear in flavours familiar to ours, and some kind of organisation for it to appear in any flavour.

He also briefly discusses strong AI, is critical of functionalism in this context and (it felt to me) he agrees with Searle's criticism (Chinese room etc.): consciousness depends on the substrate, not necessarily in a very wet sense but on the often overlooked intricate details of organisation at the very low level. (This opens questions about the relationship of computation and physical base in biological systems in general, not touched in the book.)

But the book as its bulk matter discusses animal evolution and the appearance of selves on various branches of the evolutionary tree, also briefly plants. Mixed with descriptions of underwater events, narrated by the author, I find the book very enjoyable, occasionally almost meditative.

[Lata · Rating 4 out of 5]

The author poses some really interesting questions about cognition by taking us from the development of single-celled creatures all the way to mammals. The author has an engaging style, and makes his material really interesting. He points to fossils and experiments performed with present day invertebrates to postulate behaviours and experiences of long-dead creatures, and from there to gradually build a picture of thinking and feeling based on actions, reactions and experiences.
The author refuses to simply take the traditional route that only humans can think and feel, as researchers have determined some really interesting things from arthropods, cephalopods (Adrian Tchaikovsky’s octopodes in Children of Ruin get a mention here), and other sea creatures.
He also asks what our responsibilities are with respect to certain kinds of research on our fellow beings on this planet.
There was a lot to think about, and honestly, I think I need to revisit this to get a better grasp on the various interesting ideas the author raised in this terrific book.

[Adam Carter · Rating 2 out of 5]

This book is a collection of interesting ideas and research that have helped the author think about consciousness, personalised using some stories about his scuba diving adventures. Many of the ideas explored were thought provoking. I thought the discussion on whether consciousness can be disunified in an animal and whether certain features of a nervous system resist immediate translation onto a computer particularly interesting. But none of the books ideas were presented in a way that was particularly novel nor were these ideas conducive to an overall compelling story about consciousness. On the one hand this books lacks the coherence and rigour that one might expect from a philosophical/empirical book on consciousness. On the other hand, this book doesn’t promise to provide more than it delivers, a modest, hopeful and well written conversation between science and philosophy. Unfortunately, I can only give this book two stars because I struggle knowing what kind of audience I would recommend this book to. I’ve read better introductions to the problem of consciousness, better introductions to biology and the evolution of animals, and better personal stories about the natural world. Moreover, I am not convinced that trying to integrate all these genres in this book paid off.

[Honey · Rating 3 out of 5]

Fascinating insight into evolution and cognition.

I enjoyed reading this although the narrative gets a bit more philosophical than scientific.
Somehow made me think more of sentience vs sapience and what constitutes sense of self and being. I particularly liked how he gives a nod to nociception and how creatures we may discredit for certain senses actually have the ability to comprehend and act accordingly and consciously.

Admittedly, not as great as his other book, Other Minds. But still a very interesting read.

[Graeme Newell · Rating 2 out of 5]

I read Smith's book on octopuses and enjoyed that one a lot but this book lacks the narrative and practicality of that book.

From the onset, this book was mired in intellectual machinations that seemed to have little relevance to the frontlines of life. This was an intellectual discussion of science and I was looking for more of the wonder and fascination of how the puzzle of life plays out in nature.

[Stetson · Rating 5 out of 5]

Peter Godfrey-Smith’s Metazoa (2020) develops the themes of his prior book Other Minds by extending an inquiry into consciousness, subjectivity, and the evolution of mind across the animal kingdom. The book operates at the intersection of philosophy of mind, evolutionary biology, and cognitive ethology, pursuing the question of how experience arises from the activity of living bodies and nervous systems. Godfrey-Smith situates his exploration within a lineage of materialist and pragmatist philosophy (Aristotle, Hume, and Dewey), while grounding his claims in comparative neurobiology, paleontology, and direct observation of marine life. Nonetheless, the fact that he is ultimately a philosopher is rather salient to one's reading experience.

The book unfolds as a phylogenetic journey through the “metazoa” (Animalia) tracing successive evolutionary innovations that scaffold the emergence of sentience and cognition. Beginning with the transition from single-celled life to multicellularity, Godfrey-Smith emphasizes how animal embodiment, motility, and environmental responsiveness already instantiate primitive forms of agency (ideas Kevin Mitchell develops in Free Agents: How Evolution Gave Us Free Will). He then examines sponges, cnidarians (jellyfish, anemones), and ctenophores, where nerve nets and contractile tissues inaugurate new forms of coordinated behavior. The bilaterians mark a decisive threshold: centralized nervous systems and bilateral symmetry establish the architecture for complex sensorimotor loops, proprioception, and the distinction between self and world. This is terrain very similar to readers of A Brief History of Intelligence: Evolution, AI, and the Five Breakthroughs That Made Our Brains (see my review -> https://www.goodreads.com/review/show...). It also implicitly emphasizes how important structure-function relationships are in the evolution of the brain and the dynamic conversation between genomes, soma, and the environment.

Throughout, Godfrey-Smith treats mind (subjective experiences hosted by the brain) as a graded, processual phenomenon rather than a binary possession. Fish, crustaceans, and insects exemplify intermediate stages in the elaboration of cognition, with varying degrees of integration, memory, and problem-solving. Particular attention is given to the cephalopods, whose distributed nervous systems highlight the possibility of “decentered” forms of subjectivity, contrasting with the hierarchical integration of vertebrate brains. With mammals and birds, the account culminates in forms of sociality, affect, and reflection that prefigure the human case, though without presuming a teleological progression.

Methodologically, Godfrey-Smith advocates a naturalistic “philosophy in the field.” His observations of marine organisms near Sydney Harbor are not anecdotal but exemplify an empirically attuned phenomenology of animal life, one that situates philosophical reflection in embodied encounters. Against Cartesian dualism and computationalist abstractions, he argues for seeing mind as continuous with life, emerging from the dynamic interplay of nervous systems, bodies, and environments. Consciousness, in this framework, is less a discrete property than a mode of being enacted by certain organisms through their capacities for perception, action, and affective engagement. This framing appears more accurate than alternatives but is also unhelpfully vague.

The book has limitations when assessed against more intractable philosophical concerns. While Godfrey-Smith is persuasive in portraying the gradual elaboration of cognitive capacities, his framework tends to conflate explanatory progress in neuroethology with metaphysical resolution of the “hard problem.” That is, the transition from coordinated action to felt experience is richly narrated but remains conceptually opaque, though it is plausible the "hard problem" is a misleading frame altogether. Godgrey-Smith's Deweyan emphasis on embodiment and behavior foregrounds the functional role of consciousness, but critics will argue that the qualitative dimension of experience or what philosophers since Nagel have called the "what-it-is-likeness" is bracketed rather than explained. Given the nature of subjectivity, it become difficult to tackle this question with precision, relying on contentious assumptions rather than shared premises. I have my view, but I understand why it is not shared by others.

Further, Godfrey-Smith’s pragmatist orientation sometimes risks dissolving ontological questions into methodological ones. By emphasizing continuity and avoiding hard demarcations, he produces a rich descriptive taxonomy of animal minds, but some readers may feel that the absence of a stronger theoretical stance on the metaphysics of consciousness (e.g., panpsychism, emergentism, or physicalist identity theory) leaves the account underdetermined. Erik Hoel, for instance, would assert that a theoretical model is absolutely necessary for explaining the relationship between inputs and output with respect to centralized nervous systems, which themselves probably elude reductive methods due to their recursive nature.

Metazoa advances a pluralistic and evolutionary account of the mind: consciousness is a layered, heterogeneous phenomenon, arising from the history of animal life rather than a singular event. It challenges readers to reconceive mentality as immanent to the fabric of living processes, distributed across phylogeny, and intelligible only by integrating philosophy with the sciences of life. I recommend it only to reader already well-versed in debates about the evolution of nervous systems and philosophy of mind.

[The Inquisitive Biologist · Rating 5 out of 5]

Author of the bestseller Other Minds, Peter Godfrey-Smith returns to the topic of subjective experience, consciousness and minds, charting the evolution of life's ability to behold itself. Read my full review at https://inquisitivebiologist.com/2020...

[Dan Graser · Rating 4 out of 5]

I was pleasantly surprised by this volume from philosopher Peter Godfrey-Smith in that it brought some welcome clarity to the issue of consciousness and the origin of what we know to be the mind in the natural world. Oftentimes - and I realize how general a remark this is - philosophers discussing something that is mainly the province of scientists turns the discussion into a linguistic and syntactical rat's maze with no end and no conclusions, even if they manage to agree on terminology (they never do). A lot of people approach books in this area from philosophers with trepidation however I have to say as someone with a very biologically centered materialist view on this, you have nothing to fear from this volume.

Here, proceeding from a very materialistic perspective on the mind, he examines how varying degrees of sensation, response, and adaptation have transformed the nervous systems, and as a result, the ability to call something a mind from some of our most distant ancestors. A particularly interesting focus for me was on nociception in creatures we don't credit with having a sense of pain. That we begin with some of the most basic sea creatures - mollusks, shrimp, starfish - is evidence of how comprehensive a look he is taking at the notion of having a mind and being conscious. We are then treated to a developmental history of these features both from fossil and naturalistic evidence and also from his own personal experiences observing these creatures in the waters around Australia.

I'm not totally sure I agree with his final conclusions, embracing the "walled off garden" notion from Wittgenstein (a remark that this previous philosopher meant as a pejorative), however I have to say I haven't yet read a book that dealt with a subject area so fraught with tedious and tangential terminological issues that read with such clarity and openness of opinion. It is certainly the case that humans have been very solipsistic in their view of what could constitute a mind among our distant cousins and ancestors, and so far, Peter Godrey-Smith is the best guide to take you through this development while also framing the discussion - philosophically speaking - with cogency and clarity.

[Stephen · Rating 5 out of 5]

Epistemology is one of my many weak points. There were places in this wondrous book that waxed too philosophical for me to follow and I confess got skimmed. The new paleontology, the biology, the neuroscience, the animal behavior sections are moving and eye-opening They are also witty, as in the description of a shrimp with multiple appendages "a Swiss army knife" or of another shrimp with a head "festooned with golf clubs and party lights." The author describes an experiment showing that bees, with brains of 1 cubic mm volume, can quickly learn to follow two-stage decision trees. A central argument is to toss out the old phrases we learned about "higher animals," and "lower on the tree of evolution." This book is a scientific complement to the poetry of Henry Beston decades ago in The Outermost House: A Year of Life on the Great Beach of Cape Cod

“We need another and a wiser and perhaps a more mystical concept of animals. Remote from universal nature and living by complicated artifice, man in civilization surveys the creature through the glass of his knowledge and sees thereby a feather magnified and the whole image in distortion. We patronize them for their incompleteness, for their tragic fate for having taken form so far below ourselves. And therein do we err. For the animal shall not be measured by man. In a world older and more complete than ours, they move finished and complete, gifted with the extension of the senses we have lost or never attained, living by voices we shall never hear. They are not brethren, they are not underlings: they are other nations, caught with ourselves in the net of life and time, fellow prisoners of the splendour and travail of the earth.”

[Sophia · Rating 5 out of 5]

So far, this is the only philosopher that not only can I stomach, but I genuinely enjoy reading and agree with his ideas. In this book he lays out the case for gradual sentience across species with a particular focus on sea creatures that could most resemble our evolutionary ancestors.

As with the first book, this is a really pleasant read that feels like watching a nature documentary, painting a picture of seascapes populated by the most amazing creatures. In between the discovery of different species there’s the thread of speculation on what kind of mind these animals have, and how that relates to our own feelings of consciousness and sentience. While the first book approached this topic by focusing on octopuses, here he expands on other minds that we might not specifically label as “sentient” but really challenge any notion of a clear line between sentient and non sentience.

Unlike almost every other philosopher that I’ve read, Godfrey-Smith is amazingly concise and crystal clear. While he’ll reference other philosophies, he’s careful to explain the core ideas without digressing. He generally relies less on other works and more on our own common experience, and carefully explains scenarios in which this is helpful, and others in which our own perspective is biasing our understanding.

Furthermore, his understanding of science is rock solid. He covers a lot of neuroscience (my field), and both explains concepts simply and correctly. He presents really relevant studies involving split brain patients and such that really help explain his idea that consciousness as we know it is a fluid experience that depends on what brain areas you are currently accessing and what that therefore means for species with and without such areas.
(To be completed later)

[Mo · Rating 2 out of 5]

Quite disappointed by this book. My high expectations after reading ‘Other Minds’ by the same author (read review here) weren’t met in the slightest. However, there was some interesting food for thought, so I’ll start off with that.

Subjects that interested me

- How animals went from passive eating (diffusion) to grazing to hunting
- How growing a bigger body in evolution could be achieved through either multiplying structures or enlarging them
- The crustacean body: adding body parts as a solution to many evolutionary issues
- Complexities of arriving on land for aquatic animals: swallowing, being able to move fast (fins --> legs), breathing (gills --> lungs), egg laying in dry areas (--> amniotic shell around egg / mammal solution).
- The distinction of different senses by seeing what effect an action has on that sense: it will have a big effect on touch and vision, but a smaller effect on hearing.
- Possibilities of measuring pain in animals: behavioral reaction, behavioral trade-off, chemicals.
- Theories about the brain of the octopus: do all arms have an independent brain or do they only work together and with the head? The writer proposes a ‘switching between whole-animal centeredness and a glimmer of autonomy in the arms, or some of them’.
- Other facts about how the left and right brains are (dis)connected in animals and how these animals deal with that.
- The complexity of appointing feelings and experiences to animals. It is really hard to empathize with animals that are so different than us, and we have no clue how to measure their intelligence or consciousness.
- A gradualist view on sentience which the writer proposes: evaluation and sensing for example, are two different things. Maybe insects have evaluative experiences but do not have sensory ones (cannot ‘sense’ pain for example). And maybe this is evolutionary useful because insects are often very social animals and pain is not that useful, they should ‘soldier on’. This was really the most interesting and new part of the book for me. The writer says every animal (and even plant) has ‘minimal cognition’, since it is able to feel its surroundings in the most basic way (it should be able to respond to food, for example). But sentience in more complex ways has come into being gradually and is very different for distinct animal groups.

Disharmony

- Specificity: as a reader it feels like the writers wants two conflicting things: both to give a broad view on the evolution of consciousness throughout the evolutionary tree, but also to share many stories, fun facts about particular animals. The latter is maybe more fun to read, but really stops the flow of the timeline.
- Complexity: the consequence is that some parts are really basic and even unnecessarily simplified (from a biologist point of view), while other parts are very complex. You should be prepared to learn up to 5 new words in one page (which, again, stops the flow of the book). At the same time, when explaining what an evolutionary tree is, you are longing for an explanation on how evolutionary trees are created by us, how certain they are, and what they are based on (morphology, DNA, etc.). Traits that are gained but then lost and homology (similar structures, but separate evolutionary lines) are also important concepts which are skipped. ‘Populations occasionally split in two’ is an example of an unncessary simplification: what is actually meant by this splitting into two, how does this work?
- Viewpoint: what is also conflicting is the scientific and philosophical viewpoints. These can go hand in hand of course but sometimes you really lose the message of the book (how did consciousness evolve) in the more broad question (how should consciousness be defined). He covers many theories and raises more questions than he answers. Then suddenly he brings up it will be hard finding a solution to ‘the problem’ at which point he has done a poor job at explaining what problem he is talking about. The first part is called ‘protozoa’ but is actually more about the philosophical viewpoint of the writer in preparation for the rest of the book. Which is … peculiar.

Unclarity

- These conflicting things described above are mostly annoying because you expect something different upon reading the title. I would suggest ‘in search of consciousness..’ or something at least more philosophical / less conclusive.
- The structure of the book also leaves room for improvement. 1) A wrap-up of each chapter would have helped a lot, to know where we stand and what we have learned so far, but no, the writer prefers to end each chapter with a personal experience which is suppose to be a really fitting and wholesome ending but feels very forced. 2) The order in which he mentions different groups of animals but also species in more detail remains a mystery to me. It could be evolutionary timeline (but then why mention animals that live nowadays as an example?), or only the evolution of new traits related to consciousness (but then there are multiple paths from the same origin; why choose to mention one before the other?).
- If the writer does not have any issues with teaching some terminology to his readers only relevant for one page, maybe it would also be an idea to explain the Greek origin of these words, since that would make it more understandable and easier to remember (such as ‘acoel’, ‘polyclad’ etc.).
- The pictures were nice, but I think there could have been many more for the purpose of clarity (one big evolutionary tree in the beginning, for example, and pinpointing where we find ourselves on this tree per chapter). Graphs, pictures of different eye structures / nerve systems, you name it, I want it.

In short, I think the writer should have thought more about his intention and public before writing this piece. The book went in every direction but a clear one, and therefore lost both my interest and its potential for the subject.

Quotes
“Over 100 million ribosomes [stations where protein molecules are assembled] could fit on the period printed at the end of this sentence.”
“[Brain processes] are not causes of minds; they are minds. Brain processes are not causes of thoughts and experiences; they are thoughts and experiences.”

[Samuel Buckley · Rating 3 out of 5]

I was on the verge of giving this book 4 stars but I think 3 is fair enough from my point of view. I loved how Godfrey-Smith wrote about the evolutionary aspects of animal life and consciousness, giving fascinating details and telling the evolutionary story in a very creative and endearing way. However, I could not engage with the philosophical and psychological aspect of the book (this should have been expected, as the author is a philosopher of science) as I found the concepts pretty hard to grasp and slightly boring at times. However, overall an engaging insight into the evolution of animal life and the story of how consciousness and the possibility of higher sentience in other animals came to exist

[DRugh · Rating 5 out of 5]

A layman’s review of biological history from protozoa to land animals, including humans. Godfrey-Smith emphasizes individual experiences and the formation of consciousnesses. The book gave me a deeper appreciation of life’s web.

[Ben Zimmerman · Rating 2 out of 5]

I had previously read, Other Minds: The Octopus, the Sea, and the Deep Origins of Consciousness. Metazoa, compared to that book, attempts to take a wider perspective on the emergence of animal minds. The main goal of Metazoa is to try to make progress into the guesswork behind what other animal minds are likely to be like, which has ramifications for ethics and how we think of minds and experience more generally. This work requires some way of bridging the gap from materialist views of biology to the experience of minds, which has traditionally been described as "the hard problem." Godfrey-Smith provides his thesis of how to tackle this problem towards the beginning of the book: "The evolution of complex life naturally gives rise to the mind, through the growth of purposeful action and sensitivity to the environment." So to me, it sounded like he was saying that the best way to guess about what it is like to be another animal is by studying an animal's behavior and its sensation/perception systems, which, to be honest, I personally had a hard time seeing how that is any different from the usual approach.

Because he wants to link mind with the evolution of complex life, he weaves discussion on phenomenology through a gradual discussion of the evolution of life.

The first chapter, protozoa, discusses the concept of a "self" as being a fundamental building block of life. The argument is that cells can be thought of as selves because they organize and control storms of electrical and chemical activity to meet their own needs. Even these single cells have ways to sense their environment and to move in accordance with those sensations, which gives the protozoa agency. Godfrey-Smith argues that the colors and flavors of this agency define what the mind looks like.

For example, the glass sponges and corrals, the subjects of the next two chapters, have the limited ability to adaptively respond to their environments. Godfrey-Smith shows through the discussion of polyps how action programs, like grasping, can be co-opted for movement and drive evolution.

Godfrey-Smith proposes that subjectivity, which is an important part of how we think of minds, evolves alongside of agency. As the nervous system develops along with early muscles in corals, anemones, and jellyfish, animals gain the ability to coordinate activity across the whole animal, which lead to more sophisticated possibility of action.

In the one-armed shrimp, Godfrey-Smith discusses arthropods and makes the argument that at this level, forms of available action require the animal to understand the difference between actions made by itself compared to actions made by other things in the world. He gives examples of eyes moving around a room, where the sensations on the eyes are changing very rapidly, or when a shrimp momentarily grabs itself with an arm, but then lets go. These kinds of actions require that there is some subjective knowledge, that there is a "subject" that does these things, which is different than simpler actions - like say using a single swimming action to go towards a light or a chemical gradient.

Godfrey-Smith talks about how in the Cambrian period, about a 540 million years ago, animals started to scavenge and predate on other animals for the first time, which drove the evolution of more sophisticated action and sensing programs that give rise to this new, necessary "point-of-view."

Godfrey-Smith is doing all this work in making us start to feel like shrimps and spiders are similar to us in their probable sense of subjectivity, but then he seems to use the octopus to remind us that, in fact, there are reasons to think that animal minds would differ quite substantially. He uses the structure of the octopus nervous system, an animal whose anatomy and behavior he knows well, as a case example. The octopus has a much more decentralized nervous system than ours, with ganglia controlling each leg, but connected to each other. This discussion dives into a deeper question of how disconnected regions may act as separate selves for separated actions, but may merge when actions are coordinated, and brings in evidence from split brain patients and other examples in nature of animals with minimal connections between major brain areas.

We get even closer to our own brains in the discussion of the centralized vertebrate brains that began in fish. Through this section there is discussion on other sensory abilities, especially electrosensing, which sort of clunkily leads into philosophical thinking about fields that lies at the basis of Godfrey-Smith's speculations about what defines consciousness. This was the notion that I personally found myself most vehemently disagreeing with and even seemed contradictory to other statements that Godfrey-Smith made, but he continues returning to the idea for the rest of the book, even using it to justify why an AI agent isn't allowed the same consciousness as his beloved animals.

The account of biological evolution is more coherent than the mechanistic discussion of consciousness and picks up again with the transition of animals from sea to land, which created another burst of animal innovation. I really liked the sense of inevitability that we get from the account. The chemical properties of water make it necessary for life to first evolve in the ocean, but once life is complex enough, it may be capable of adapting to the land. Adapting to the land comes with huge rewards because the amount of energy available from the sun and oxygen levels are much higher.

The transition to land opens up a new field for evolution to adapt new kinds of bodily actions and ways of manipulating things, as well as new relationships to plants and other animals. This part of the book also spends a lot of talking about animal cognitive abilities and how different animals solve different types of problems. That topic turns into a discussion of pain, emotions, and moods, and provides evidence that even arthropods and gastropods may experience these things. I really appreciated the introduction to behavioral paradigms used to study pain, which included observations of tending wounds, pursuing analgesics, accepting pain more readily in situations where there is some additional future reward or threat, and being more pessimistic about the possibility of reward after injury. I also liked that Godfrey-Smith proposes a plausible reason why some animals may not benefit from evolving pain - particularly short-lived animals, like adult insects, who need to reproduce extremely quickly before dying. However, I sort of felt like Godfrey-Smith was trying to sneak something past me, because he would consistently remind us that we shouldn't simply trust animal behavior, since we have a tendency to view behavior too much from our own perspective…but then he would support all of his own arguments about animal experience through behavior.

The end of the book introduces one of the last fundamental elements of mind, which he calls a difference between online and offline processing. This concept differentiates making actions in the present vs. modeling the future and the past through learning. He connects this process to sleeping and especially REM sleep, with the implication that animals that have something like REM sleep probably have something like the ability to "go offline" and imagine or remember, including states that exist in cephalopods. He ends with a straightforward discussion of ethics that should reconsider animal pain and experience - although, I thought he was pretty conservative with his recommendations after the rest of the book…he explicitly says, "the aim of this book is not to argue that we need to radically change our behavior towards animals of those kinds” …referring to insects, gastropods, and the like earlier.

[Tom Ewing · Rating 4 out of 5]

What is it like to be a bee? Or a shrimp, a sponge, an octopus, or any other animal? Godfrey-Smith’s exploration of this fascinating question is welcoming without being glib - he’s always careful to point out when he simply doesn’t know an answer. Which is often, as the central problems here - of where and when the animal capabilities of sensing and action shade into experiencing and a sense of self - are famously hard.

The book is strongest in its first half, advancing steadily through the billions of years of sea-bound evolution, building a good case that consciousness in the sense of possessing an “experiential profile” is an early and useful adaptation. It’s a thrilling story of how animals gradually learned to get shit done and the role living as an experiencing creature played in this.

Once we get onto land the tone shifts a little - less illustration via Godfrey-Smith’s own scuba diving experiences, more citations of experiments. Some of these experiments are fascinating - on the sadness of bees and the dreams of rats - but the combination of intimacy and grand scale that drives the earlier part is lost. Also, there’s just too many animals crowding the scene. “What was it like to be a dinosaur?” he asks at one point, then drops the thread almost immediately, to the great regret of my inner 5-year old who still would very much want to know. It’s not too surprising when Godfrey-Smith reveals at the end that a lot of the juicy stuff on the nature of primate and human experience is being saved for a sequel.

Still, there’s a lot to chew on just in this book, which finishes with a thoughtful and lucid summary of what Godfrey-Smith believes about mind, why he believes it and why brain uploading extropians are full of shit. Well worth a read.

[Martin Riexinger · Rating 3 out of 5]

A book that wants to achieve too much, and disappoints in the end.
The author (a philosopher of science, not a biologist) wants to underpin his idea that consciousness (in its various degrees) is not something that is added to the animal body but one of ways in which it operates, like movement, feeding and sensing. He attempts to do this with references to a variety of animals which represent stages when something new in the cognitive sphere happened concomitant with other evolutionary changes. The third aspect of the book wich is noteworthy that the author's hobby is scuba diving, as result of which he is very interested in marine fauna.
This accounts for both the fortes of the book and the weakness of the final chapters. Referring to sponges, corals and jellyfish, his favorite the octopus, shrimps and fish how neuronal and brain activities emerged in in interaction with the evolution of muscles, sensitive organs and skeletons (or their disappearance) and led to the development of specific abilities.
When it comes to terrestrial life, the enthusiasm gets lost, the examples are dealt wirth rather superficially, and the digression on the question in how far plats are organisms where individuality is less easy to determine than in animals, should have place in the start. Most disappointing is that the development of both the avian and the mammal (in particular primate) brain are given fa less attention than those of the maritime animals.
Although disappointment prevailed in the end, I read the first parts with great interest and learnt a lot, therefore ***

[Ben · Rating 3 out of 5]

I enjoyed this one.

Great scientific book.

I feel that, although this book was great, I would recommend instead these books instead:
The Soul of an Octopus: A Surprising Exploration Into the Wonder of Consciousness
Other Minds: The Octopus, the Sea, and the Deep Origins of Consciousness
Fathoms: The World in the Whale
Spying on Whales: The Past, Present, and Future of Earth's Most Awesome Creatures

2.9/5

[Illiterate · Rating 4 out of 5]

Godfrey-Smith uses the evolution of consciousness to defend a gradualist view of mind, dissolve the mind-body problem, and promote a materialistic monism.

[Glen Schroeder · Rating 5 out of 5]

Godfrey-Smith seems to get a lot of flack for being a philosopher discussing biology. But I think the best works are interdisciplinary and often the ones that lead to new insights and fresh questions. For a philosopher, he knows his science (at least to the degree required by the subject matter). If you must critique those who write outside the bounds of their discipline, might I suggest Richard Dawkins.

All your favorite books that you’ve read throughout your life were about the human condition—this banal term worthy at best of high school sophomore English papers, and the better (more collegiate, speculative, philosophical, beautiful, etc.) works deal with this rather large idea in more sophisticated ways, and we appreciate them for that. But certainly that perspective is inherently narrow, vast in the individual perspectives of a single species. So how much more grand of a view it is when we pick up a book like this, a book whose premise is to discuss (with all the modern researches and the millennia of philosophies) consciousness as experienced by all living and evolved beings.

There is a term you must understand here: gradualism. This is the idea that evolution does not rapidly develop sentience/consciousness in this species or that, but instead enables it to develop gradually to varying degrees throughout species as advantageous to each species, adding more here, subtracting some there, as needed. Godfrey-Smith’s previous book Other Minds is all about cephalopods, their brains (which operate entirely differently than mammal, reptile, or fish bilateralism), and their path through evolution. Metazoa is a continuation of that book, and though the author spends a good chunk of time discussing octopuses and their ilk here as well, this book indeed branches out to discuss many other species (without much focus at all on mammals).

Talking of everything from dolphins to ants, bees to whale sharks, and the nervous systems of each, he eventually argues that to some degree subjective experience exists across species. (Plants are a bit different regarding the topic of mind. Read the book.) What subjective experience looks like can differ greatly of course. “If subjectivity is an important idea in making sense in the evolution of the mind, doesn’t everything with minimal cognition have a kind of subjectivity, a way things seem to it, and so on?” I think so, Peter. And all the while throughout, one can ruminate on how these ideas impact the age-old debate of monism v. dualism.

The human condition: “A likely difference between human and non-human cases is not the existence of elsewhere experience [the mind drifting away from immediate sensory experience] but the extent of its deliberate control. A feature of human cognition that really does seem to differ greatly from what goes on in other animals is something psychologists call “executive control”—the ability to direct oneself on a task, suppress momentary urges, and marshal one’s various abilities in pursuit of a consciously represented goal.”

I wasn’t even going to write a review, but how could I not. The research, the speculation, and the consideration for other species will get you every time. Give it a read and see for yourself.

[Irene · Rating 5 out of 5]

A fascinating exploration of what the limits of the mind could be. The section I found most interesting took a look at the consequences of modified brains in people who had their corpus callosum severed (surgically, to mitigate seizures), and how in some cases their brains wanted them to do two different things at the same time. Godfrey-Smith speculates that consciousness may not be a unified "thing" but rather a collection of experiences we perceive as a unified occurrence. I'm inclined to agree.

Everything we experience is manufactured by our brains reinterpreting what is perceived by our senses and hence, technically, entirely fictional. The concept of time? Made up! Our memory of what we had for breakfast? Also made up. Free will? I hate to tell you, but an illusion. Just like human languages, in all their complexity, are only very specialised abstract pattern recognition, I find it hard to entertain the idea that other animals don't have much more complex inner lives that we are able to recognise for what they are because our perception is so biased towards our own. The little section at the end dedicated to AI was thought-provoking too.

I appreciate that Godfrey-Smith brings ethical concerns into experimentation and that he doesn't seem to be motivated by proving humans are at the top of the consciousness hierarchy. I'm a lot more lax when it comes to giving other animals the benefit of the doubt because our experiences are severely limited by our senses, but I don't think you can, as an actual philosophy professor, make unsupported statements about the nature of consciousness based on an absence of evidence.

[Richard · Rating 5 out of 5]

In my review of Peter Godfrey-Smith’s book Other Minds I pointed out that he is a science writer who remembers that knowledge is only worth sharing if you don’t put your reader to sleep! Fortunately, in Metazoa: Animal Life and The Birth of the Mind his writing continues to be fascinating, full of information, thought-provoking, and interesting - all at the same time.

In Metazoa, Godfrey-Smith explores the topics of sensing and thinking by addressing the question of when in evolution did plants and animals develop these abilities. The big question is whether intelligence is something new or did it begin in small measures millennia ago.

The first problem you come upon when you discuss thinking is defining exactly what it is you are investigating. I remember reading in one of my first psychology classes that in 1923 Harvard professor Edwin Boring said that “Intelligence is what Intelligence Tests measure”. Personally, I am not sure than anyone has improved upon this definition in the past century.

One side of the thinking debate maintains that humans are the only creature on earth that has intelligence. Of course, the annual Darwin Awards find many examples that call this idea into question. On the other extreme is biopsychism, the idea that all life is sentient, able to perceive or feel things.

In this book, Godfrey-Smith does an excellent job of laying out what we know, and much of what we don’t know, about the evolution of the mind. Overall he advocates the idea for “a gradual process by which the self becomes more definite” than for a “sudden switching-on of the lights”.

There is an incredible amount of scientific and philosophical material in this book but, as I mention above, Godfrey-Smith presents it in a way that keeps you interested. An avid scuba diver, he provides a number of fascinating examples of plant and animal behavior that he has witnessed on his dives and even includes a number of great photographs his has taken.

While there are many ideas and theories presented in this book, for me the best part is that it gave me a new foundation on which to further explore what it is to be sentient and intelligent..

[Steve · Rating 5 out of 5]

A wonderful book! Continues the exploration of consciousness he started in “Other Minds” by looking at other forms of life. Great combination of biology and philosophy of mind, with lots of reasoning based on evolutionary theory. Also, the author is a great observer of wildlife. Finally, I loved his writing style - he doesn’t lecture the reader, instead he brings you along on a voyage with him. He has a definite point of view, but he is humble and is respectful to those who he doesn’t agree with. Reminds me of Darwin, and what higher praise is possible?