GUEST ESSAY: Philip Goff’s error: A review of his book, 'Galileo's Error'

By Stephen Davies 

(This is a guest essay submitted to the Metaphysical Speculations Discussion Forum, where it was extensively reviewed and critically commented on by forum members. The opinions expressed in it are those of its author.) 

Galileo Galilei. Source: Wikimedia Commons. 
British philosopher Philip Goff describes how early Italian scientist Galileo Galilei sought to explain the whole world quantitatively, and so decided to take the qualia associated with the world—such as the colors we see, the flavors we taste, the aromas we smell, the textures we feel, etc—and place it within consciousness, away from the matter where it was previously believed to be.

Before Galileo, redness was thought to be in the object perceived as red; sweetness was thought to lie within sugar. Galileo decided that these experiences of the qualities of the physical world, such as sweetness and redness, were instead to be found within the mind of the experiencer, leaving matter to be home for quantitative properties only, such as mass, momentum, velocity and the like.

What Galileo didn’t do was create a new form of consciousness dedicated to the perceptual qualities associated with the physical world. Instead, he took those qualities and placed them within our preexisting understanding of consciousness; the same consciousness where we experience emotions, thoughts, imagination, and other endogenous experiences. He simply moved into the mental domain something that had hitherto been assumed to reside in matter.

This way, sensory qualities associated with the physical world—such as redness and sweetness—were assumed to originate in the circle of mind, not that of matter. The intersection of the circles—the experiential perception of the physical world—was where these then came together.

In the overlap of the circles of mind and matter we, for example, see and taste a sweet red apple. The apple belongs in the physical world and can be described completely quantitatively in terms of size and shape and weight etc. In turn, the experience of redness and sweetness belongs in mind and can be described qualitatively by the experiencer, but not reduced to numbers.

The point here is that the circle of mind was already assumed to be there and the sensory qualities of the physical world were merely added to it. As such, the circle of mind was made bigger.

Goff’s error is to then create a metaphysical explanation for mind and matter that is based upon just this one particular intersection of mind and matter; that of the physical world and the qualities of sensory experience associated with it. He ignores altogether the rest of the contents of mind—such as thoughts, emotions, imagination, etc.—that do not arise from sensory perception.

Goff’s theory is that matter, as described in purely quantitive terms, is the entirety of consciousness in action; consciousness is nothing more than the intrinsic nature of these physical quantities and matter is what consciousness does; it is the extrinsic appearance of consciousness.

This is a huge and costly error, for he has conflated Galileo’s one addition to the contents of consciousness with the whole of consciousness. Maybe the experienced qualities of sensory perception are the inherent nature of the physical world, but there is no reason whatsoever to restrict the whole of consciousness to such a limited role. There is a whole host of other contents of consciousness that has little to do with sensory perception. Goff seems to lose all of this in his account of reality.

Idealism does not. Idealism correctly sees the experience of physicality as what it is: a particular type of the many possible experiences within consciousness (in Kastrup’s Analytic Idealism, this arises as a result of dissociated aspects of consciousness).

Consciousness is not exhaustively described or understood in terms of sensory experience—there is so much more to it! Goff’s panpsychist metaphysics in Galileo's Error is meant to account for all of matter and all of consciousness but is based on—and therefore can only account for—sensory experiences of physicality.

When setting up his theory, Goff uses the word 'consciousness' when he is actually referring to just a particular type of conscious experiences. He then says that his theory explains the role of consciousness and says it is the intrinsic nature of matter. But now he suddenly means consciousness as the whole contents of consciousness and the conscious subject.

We are not just beings that have experiences of seeing, hearing, smelling, tasting and touching. On what grounds can you coherently argue that all conscious experiences are just the intrinsic nature of the material aspects of these five senses?

In Idealism, consciousness can exist without matter, without an experience of physicality; these are optional extras. For Goff, reality is one coin with one side that is matter and the other side is consciousness; they are inextricably linked as two aspects of one thing. Matter has no intrinsic nature without consciousness and consciousness has no extrinsic expression without matter. There is no possibility in Goff’s metaphysics for consciousness without matter; it is tied to and limited by the physical world.

Goff’s panpsychism is borne out of materialism. He uses consciousness to fill a gap in materialism, the gap of the intrinsic nature of matter. Idealism puts consciousness first and foremost and matter is wholly subservient to it. For Goff, matter is still in the forefront, still limiting what consciousness can be. This is why he fails to provide a metaphysics that truly accounts for consciousness beyond mere sensory perception.

Copyright © 2020 by Stephen Davies. Published with permission.


  1. Nice dissection, Stephen, of Goff's fundamental intellectual mistake. But throughout this materialist/idealist debate, one question keeps bothering me. Are we really getting to the heart of things--the meaning, if any, of life; our purpose, if any, in living it; the empathy or compassion we should show, or not show, toward human beings and other living things--by parsing the nature of shared experience, whether it is purely subjective or has some sort of objective component? It seems to me, as an old and rapidly aging man, that what really matters in life, looking back upon it, is how we live it, whether we take it merely as a given, a brute fact to be exploited for personal pleasure or gain, or whether we see it as people like Albert Schweitzer saw it--as a gift, a mystery, a miracle which calls forth from us reverence for it and ethical commitment to enhance it. My question, in other words, is what bearing the materialist/idealist controversy, intellectually fascinating as it is, has on such personally significant matters, which seem to dwell much more on how we are to engage with and participate in our shared experiential reality than on the ascertainment of its ultimate nature or structure. Stephen, Bernardo, and readers of this excellent blog--does what I'm wondering about resonate with you and, if it does, what might be your thoughts and feelings in response to mine? Can you help me see what bearing this interesting, challenging philosophical interchange about the ultimate nature or structure of reality may have on what one might call the art of living? By the way, I suspect there is one.

    1. Materialism can tend towards a view that we are accidental biological robots in a fundamentally meaningless universe. Idealism, on the other hand - at least for me - imbues the previously mundane with life, consciousness, significance and meaning.
      One example: if consciousness is the one eye that sees through us all, then what we do to others, we, literally, are doing to ourself.
      The very act of engaging in metaphysical speculation can be, at least partly, the fulfilling of life’s purpose if we see the formation of our seemingly separate metacognitive selves as the means by which non-metacognitive Mind comes to know itself.
      What about your own thoughts on this?

    2. Thanks, Stephen, for the prompt and thoughtful response. While I agree that a philosophically materialist view of the universe can be conducive to a socially and selfishly materialist lifestyle (a "me" rather than a "we" orientation), I also take note that Schweitzer, with whom I've been spending a lot of time, indicates that he often encountered more passionate humanist action and advocacy in materialists than in many of those who claimed to be more spiritually inclined. Bertrand Russell, for example, who joined with Schweitzer in calling for an immediate ban on nuclear testing, comes readily to mind, and then there is Camus, etc. Schweitzer was leery of too much abstraction in our thinking, which he believed could draw attention away from concrete efforts to meet immediate, pressing human needs and, indeed, attend to the welfare of all living things (as we now so desperately need to do). On the other hand, Jesus, with whom I also spend a lot of time, echoed Jewish and other religious traditions in instructing us to first love God and then our neighbors as ourselves, as if the two were somehow joined at the hip--somewhat in the manner you indicate that philosophical and ethical idealism can and perhaps should be. So I greatly appreciate your suggestion that how we see the nature of the world, the ultimate context in which we live, can often have a profound effect on how we engage in living. Again, that was a really sharp and succinct essay.

  2. Consciousness naturally implies an entity, as whose consciousness. Can we ignore this vital entity aspect, the sense of self aspect? Love to share a work throwing light on how this sense of self is centrally relevant:

  3. If matter is what consciousness looks like across a boundary how can idealism do without matter, as you say?

    1. I'll take the liberty to react: if there were no dissociation, and thus no dissociative boundaries, there would be no matter, but there would still be consciousness.

    2. Bernardo's observation jibes with much of the professional and painstaking psychical research performed in the late 19th/early 20th centuries, courageously pioneering work now largely forgotten. The conclusion reached by most of these psychical researchers--among them dedicated and distinguished men and women of science, philosophy, classical literature, etc.--was that human personality/consciousness does indeed survive bodily death and finds itself in an ineffable form of continuing existence, of persisting consciousness, now unconstrained by space and time--the apparent context, if I understand it correctly, in which Bernardo's "dissociative boundaries" manifest.

  4. Seen some discussions between Goff and Kastrup, I still don't understand Goff is not admitting this error (as I also see it). As I read here Goff has revised his Gallileo's Error?

    1. Yes. It’s now ‘hybrid cosmopsychism’:

    2. Having said that, he has just tweeted: ‘I don't think I've changed my mind on anything I say in this book“?