This is a review of Philip Goff’s book Galileo’s Error: Foundations for a New Science of Consciousness. I was intrigued by the idea that we could consider consciousness to be a sort of universal fabric that comprised even sub-atomic particles. But, alas, I think Goff’s idea is not well supported by his argument. Pansychism is vulnerable to David Hume’s devastation of the mediaeval notion of ‘substance’: an ‘intrinsic stuff’ that the schoolmen thought lurked beneath the empirical qualities of matter and the experiences of the ‘soul’.

In this engaging book, Goff first shows that consciousness remains a mystery; most explanations fail when closely examined. That includes naive materialism (the claim that consciousness is nothing more than neuro-chemical events in the brain) and mind-body dualism that postulates a “ghost in the machine”. So Goff tries to bring back an old idea that unifies mind and body: panpsychism. This is the claim that the world that we have reluctantly concluded is an immiscible combination of matter and mind could be, in reality, a continuum filled by a substance called ‘consciousness’ that is ‘intrinsic’ to both matter and mind.
Why does Goff think we need a candidate for the ‘intrinsic’ stuff of the world? Because, he claims, modern science fails to tell us anything about the true nature of matter (or of experience). Since the Galilean revolution, he says, science has focussed only on what matter does using mathematical descriptions. It does not tell us what matter is. This is because Galileo changed the nature of scientific enquiry. “Physics since Galileo”, according to Goff, “has been a purely mathematical science. There is nothing beyond the equations…” (p 125).
This is a diverting claim, no doubt, but utterly mad. It suggests, for example, that the CERN collider project is nothing but a multi-billion-dollar, million-person-day random number generator. In fact, as a few hours of research will confirm, the greatest advances of 20th century physics (not to mention Newton) — such as the ideas of Bohr, Born, Schrödinger, Einstein — came not from mathematics but from intuition, reflection, imagination and speculation that formed hypotheses mathematised only later (a good brief history is Phillip Ball’s Beyond Wierd). Einstein was not good at math: he teased his discoveries out of imagining himself riding on a light wave and in a celestial elevator (see Walter Isaacson’s Einstein for an account of the development of his thinking). Arthur Eddington, whose ideas Goff later appropriates, famously confirmed Einstein’s ideas of general relativity by showing it explained facts about the physical universe (gravitational lensing) not that it formed a system of equations.
But Goff is unimpressed. The scientific account of the nature of matter, he tells us several times, is an empty circular definition of force and mass: each term defined by reference to the other.
This claim — that the physicists’ account of matter is empty because circular — is key in the book, because Goff uses it to motivate his substitution of panpsychic for physical explanations of the ‘intrinsic nature’ of things. But it is just wrong, as far as I (not a physicist) know. Wikipedia will tell you — using the same terms as your introductory high-school physics text — that force is a vector (direction + magnitude) description of a push or a pull. Mass (an adjective, not a noun) is a quality of matter (objects with mass and volume) that describes an object’s resistance to a net force. Then the physical field (electromagnetic and gravitational) also contains massless photons and neutrinos that are nearly so. I’ve tried, but I can’t find any troubling circularity in this conceptual framework. Mass is defined by its reaction to force. But force is not defined in terms of its relation to matter.
(Goff may wish to object that a “push or a pull” can be understood only in terms of a relationship to some material object and so the definition is ‘ultimately’ circular. To this objection I would say, as he says on p.88 of his book, that you have to draw a line under skeptical nit-picking somewhere. Without pushing a line or pulling ideas out of the air, I suggest the ideas of a ‘push’ or a ‘pull’ are simple, intuitive and intelligibly independent of context.)
Does this mean that in our current understanding, all matter resolves to just some disposition of force and resistance? Well, yes! E=mc^2 really is our current understanding of the cash value of matter. It is a highly successful theory, but is it unsatisfactory as Goff claims? Maybe; your satisfaction may depend on what you hoped for. Goff wants matter to have some ‘intrinsic nature’ — not just a transactional value — because he finds that tidier and more satisfying. Accordingly, he plumps for the same idea that David Hume tore apart in his Treatise on Human Understanding. He says that everything, mind and matter, may comprise a mysterious (private, ‘you’ll know it when you’ve got it’) and universal ‘substance’ that he calls ‘consciousness’ (whatever that is).
With a sort of endearing enthusiasm, Goff even summarises this peculiar argument for us without the least embarrassment, on p. 132:
Problem 1: We need a place for consciousness.
Problem 2: We have a huge hole at the center of our scientific story.
Solution: Plug the hole with consciousness.
Goff’s idea that the world comprises conscious entities has a couple of heavyweight uncles: Bertrand Russell and Arthur Eddington. Russell’s Analysis of Matter and Eddington’s Gifford Lectures deserve the reconsideration he gives them. Some contemporary physicists (e.g. Lee Smolin) are skirting the same idea about matter that Russell advanced: that ‘events’ are the fundamental character of the quantum universe.
But I think we’re better advised to reconsider David Hume’s Treatise on Human Nature. Despite his deplorable lack of quantum cred., Hume’s is a more robust and parsimonious approach to this same problem of matter and mind, prompted by his rejection of Descartes and the idealist philosophers. Philip Goff claims (p. 134) that panpsychism is the simplest ontology: “To deny panpsychism one would need a reason for supposing that matter has two kinds of intrinsic nature [for objects inside and outside brains] rather than just one.” But Hume replies: we can make it even simpler by assuming no ‘intrinsic nature’ at all?
Hume applies the ‘Occam’s razor’ approach that Goff endorses earlier in his (excellent and entertaining) treatment of dualism and materialism. Hume will have no more entities in the world (of matter or mind) than necessary and observable. Specifically no mysterious and intrinsic “substance” undetectably underlying the impressions we have of the world in which the ‘accidents’ of experience — colour, texture, temperature etc. — inhere. We know nothing of the world, says Hume, but these impressions; consciousness (thought, soul), too, is nothing more than a train of these impressions without any ‘intrinsic’ conscious substance in which they inhere. (I take it Hume would support the idea that consciousness is an illusion emerging from our experience of this train of impressions).
I don’t pretend to catch Philip Goff in any contradictions and I enjoyed his summary of the philosophy of mind in the first chapters of this book. I share his disappointment (as do many physicists) about the unsatisfactory weirdness of current quantum field theory and the stultifying recent confirmation of the ‘standard model’ of particle physics. I hope for much better ideas in the future and agree that they’re unlikely to emerge from simply more beautiful math. But I’m less persuaded by Goff’s metaphysics than by Hume’s more modest and more testable claims. Even after reading his book, I see no alternative to materialism and I’m not un-comfortable with an explanation of conscious experience that explains it as an ‘illusion’ emerging from physical processes in the brain.
In the last chapter of his book, modestly titled: Consciousness and the Meaning of Life, Goff leverages his dismissal of mind-body dualism — now seen to be congruent with blinkered Galilean science — to attack global-warming skepticism for refusing to accept the apparent consensus of the same physical science. He references with approval Naomi Klein’s excoriation of Francis Bacon (!) for “convincing Britain’s elites to abandon, once and for all, pagan notions of the earth as a life-giving mother to whom we owe respect and reverence…” He worries with Max Weber that “the modern scientific worldview… seems to present us with an immense universe entirely devoid of meaning… “ and that economic globalization has “eroded many traditional forms of life; international chain stores have conquered the centers of communities; advertising now fills all corners of public space. Where local beauty is preserved, it is only as a quaint museum piece for globe-trotting tourists.”
But I can’t see how panpsychism supports any of these fashionable opinions. So I’d like to conclude by allowing David Hume to deliver a quietus to that quaint idea (from An Abstract of A Treatise on Human Nature)
“…the soul, as far as we can conceive it, is nothing but a system or train of different perceptions, those of heat and cold, love and anger, thoughts and sensations; all united together, but without any perfect simplicity or identity. Des Cartes maintained that thought was the essence of the mind; not this thought or that thought, but thought in general. This seems to be absolutely unintelligible, since every thing, that exists, is particular: And therefore it must be our several particular perceptions, that compose the mind. I say, compose the mind, not belong to it. The mind is not a substance, in which the perceptions inhere…”
“We have no idea of substance of any kind, since we have no idea but what is derived from some impression, and we have no impression of any substance either material or spiritual. We know nothing but particular qualities and perceptions. As our idea of any body, a peach, for instance, is only that of a particular taste, colour, figure, size, consistence, &c. So our idea of any mind is only that of particular perceptions, without the notion of any thing we call substance, either simple or compound.”