Dr Sabine Hossenfelder is a theoretical physicist working as a research fellow at the Frankfurt Institute for Advanced Studies. Her research focuses on the foundations of physics, but she is also interested in philosophy and sociology of science. She has been published in influential publications such as Scientific American, New Scientist, Quanta Magazine, Nautilus, and Aeon. You can find her personal website here and her blog here.
Professor Massimo Pigliucci is a philosopher working at The City College of New York (CUNY). His research focuses on philosophy of science pseudoscience, philosophy of biology, and the relationship between science and religion. He is a vocal critic of pseudoscience and creation and an advocate for secularism and science education. Some of his publications are: Tales of the Rational, Denying Evolution: Creationism, Scientism, and the Nature of Science, and How to Be a Stoic: Using Ancient Philosophy to Live a Modern Life. You can find his blog here.
Dr Hossenfelder and Prof Pigliucci have both recently published posts on panpsychism on their respective blogs (here and here). They are critical of the theory, denouncing it as a New Age theory (Prof Pigliucci) and expressing scepticism about philosophers talking about elementary particles (Dr Hossenfelder). However, both have offered a version of panpsychism that most panpsychists would not accept – less like ‘no true Scotsman’ and more like ‘strawman’!
Dr Sabine Hossenfelder
Dr Hossenfelder starts off by comparing panpsychism to elan vital or vitalism – an outdated theory that aimed to differentiate living and non-living organisms by postulating a non-physical element that distinguishes them. Vitalism has been mostly rejected as a theory in the early 19th century, but ultimately completely abandoned in 1931.
Although at first glance, it might seem similar to panpsychism, I fail to see what connects them. Vitalism was proposed as a scientific theory, one that could be empirically tested. Panpsychism is a philosophical theory whose aim is not to be empirically testable. Contemporary panpsychists, while believing that panpsychism is compatible with our scientific worldview, are often critical of the claim that everything in reality can be observed and empirically tested.
For instance, the motivation behind Russellian panpsychism is that science only gives us explanations of how entities behave in space in time, without telling us what those entities are in and of themselves. (This brings to mind Kant’s noumena, though panpsychists certainly do not have to be Kantians in order to be panpsychists.) Some panpsychists, however, have presented versions of the theory inspired by scientific research or versions that are potentially testable (maybe William Seager and Giulio Tononi).
Personally, I am not really interested in whether they are science-based or testable. The role of philosophy is not to supplement science or to submit itself to its standards of what makes a valuable theory. Panpsychism is, in my opinion, strong enough to be considered as a theory based solely on the arguments in its favour.
Anyways, turning back to Dr Hossenfelder’s post: she claims that elementary particles cannot be conscious because that conflicts with evidence. When a particle is collided, all of the variants in which it exists will be produced as a result. If the panpsychist wants the particle to be conscious, the minimum expectation should be that said particle can change (i.e. have more than one variant). If an electron, for example, could have thoughts (and thus change), physicists would have observed that in particle collisions because it would change the number of particles produced in collisions, so electrons (or any other particles) are not conscious.
If the panpsychists argues that there are even more fundamental particles – that physicists have not yet discovered – and claims that those are conscious, that would not help the panpsychist’s case since consciousness would be ‘hidden’ – it would take a lot of energy for us to access it. This is incompatible with our brain, who uses consciousness at lower energies.
There are several problems with her assessment of panpsychism:
- Panpsychists do not necessarily claim that particles are conscious, we claim that whatever is fundamental is conscious. She addressed the case in which there are even more fundamental particles, but not the case in which something else is fundamental (spacetime, strings, take your pick).
- Why would the panpsychist have to postulate that there is more than one thought (and thus more than one variant) in a single particle? The complexity that arises in our brain is not based on the many variants of a single particle, but on the causal structure obtaining between the particles that make up our brain (for example). Single particles could have single thoughts that create complexity when they feature in an appropriate causal structure.
- Thinking a bit more abstractly, the mental content of a particle can be strongly determined so that it always manifests in the same manner, whether or not it features a single thought or multiple thoughts. Perhaps every particle-variant is associated with a particular mental-variant.
Ultimately, though, I do not know enough about particles or their collisions in order to competently talk about this. My aim is simply to show that there are versions of panpsychism that avoid this worry, either by addressing her counterargument or by not making claims about particles at all.
Professor Massimo Pigliucci
Prof Pigliucci starts off by being baffled that serious thinkers, such as David Chalmers and Christof Koch, take panpsychism seriously. He also compares panpsychism to vitalism, which I have already addressed here. Importantly, though, he criticises Thomas Nagel’s view that panpsychism wins by default because it is ‘the last man standing’ since neither physicalism nor dualism have offered a satisfying account of consciousness. According to Prof Pigliucci, this is an argument from ignorance: science has not given us an account of consciousness so science never will!
The problem is: that is not what Nagel and other panpsychists are saying at all. We are saying that it is in principle impossible for science to even begin to address consciousness. Science approaches the world from a third-person perspective, giving us descriptions of objects based on how they relate in space in time, without giving us any information on what those objects are in themselves (as I have stated above). But one does not need to resort to some intangible, non-relational phenomenal properties or qualia to make this argument. Instead, Nagel says the following:
I have a point of view, a perspective from which I ‘look at’ the world. I make statements about my own point of view in the form of: ‘there is a laptop in front of me’ or ‘I am sitting on the chair’. This perspective is what constitutes subjectivity. Objectivity, on the other hand, involves moving away from any particular subjective perspective and giving us descriptions of the world that are accessible to all (sufficiently sophisticated) subjects. So, a more objective description might be: ‘there is a laptop on the desk’. While ‘there is a laptop in front of me’ is only true for me, ‘there is a laptop on the desk’ is true for anyone in that room, for instance.
Nagel even anticipates the counterargument from his critics, that there might be a more objective way of describing a particular subjective perspective (e.g. ‘the laptop is in front of the visual field; in the centre of the visual field; etc.). However, no amount of third-person data can give us an answer to the question of what it is like to be me as me since nobody else can occupy the unique perspective that I have on the world. In this sense, Nagel’s argument is similar (though not identical) to Frank Jackson’s famous Mary argument.
Thus, it is not merely the claim that science does not know now so it will never know – it is the claim that science cannot in principle know. Of course, panpsychism does not necessarily follow from this alone (see the next chapter of Nagel’s Mortal Questions!), but it is important to emphasise that panpsychists are not employing an argument from ignorance when motivating their theory.
Next, Prof Pigliucci examines a definition of panpsychism and asks the following questions: Does that mean that my iPad is conscious? Does that mean that the coffee I drank is conscious? Does that mean that every atom or electron in the air around me is conscious?
The answer is: not necessarily. Panpsychists differ in this regard, but I doubt that any of them would say that coffee is conscious. The ontology that we employ might be sparse: only fundamental entities (whatever they are; not necessarily particles) and living organisms are conscious. The difference, again, is the relevant causal structure: the brain has a structure that enables consciousness to (weakly) emerge, but coffee does not. That is, the panpsychist does not have to claim that anything other than what we already consider to be conscious – is conscious (well, plus fundamental entities).
After that, Prof Pigliucci attacks the genetic argument for panpsychism, which is summed up as the claim that nothing can bring about something which it does not already possess (ex nihilo, nihil fit). So, if consciousness is present at higher levels (e.g. the human brain), then physical matter must already contain some basic form of consciousness. He criticises this argument by claiming that ‘consciousness’ could be replaced with ‘life’, ‘the universe’ or ‘the laws of nature’, which would show how absurd the argument’s structure is. That is, we could make the same claim for any qualitatively novel physical or biological phenomenon, according to Prof Pigliucci. Ultimately, he claims, the genetic argument reduces to an argument from ignorance or from personal incredulity.
I think that this is a false analogy. Consciousness does not have the same ontological status as ‘life’, ‘the universe’ or ‘laws of nature’. Out of all of them, only consciousness is about the first-person subjective perspective. The panpsychist would never agree that consciousness is of the same kind as ‘life’ since ‘life’ and how it came about are physical processes. The panpsychist does not have to claim that ‘life’, for example, is also irreducible to the purely physical. We only claim that the conscious element of life is irreducible (a small but important distinction). If the panpsychist were to identify ‘consciousness’ with ‘life’, they would simply accept that life can be fully explained in physical terms. I think that we can consistently claim, however, that ‘life’ is explicable in purely physical terms and that ‘consciousness’ is not – one involves subjectivity, the inner ‘what-it-is-likeness’ of being, while the other does not (at least not necessarily).
Similarly, the universe might have come out of nothing, out of a pre-universe, or have always been present – no reason for the panpsychist to claim that this is also irreducible to physical facts! We precisely think that consciousness is different and that it must be present at lower levels because the subjective character of consciousness cannot be reduced to purely physical terms. This involves two commitments: the first being that consciousness is irreducible in that sense, the second being that radical or strong emergence is impossible (i.e. something coming out of nothing). That is all you need for panpsychism, really.
If we could observe a different, lifeless universe while not knowing that we are conscious (very abstract but bear with me), we might be able to fully explain it in physical terms and we might not have a reason to postulate panpsychism at all. That is unless you ask: what are all those relations that we are describing grounded in? Then, you might want to answer: ‘an intrinsic nature’, but maybe consciousness would not be the first candidate to play that role that pops into your mind (since we do not know that we are conscious in this absurd scenario). You might say that the intrinsic nature is some sort of ‘potentiality’, for instance (whatever you might mean with that). As for the laws of nature – that is a can of worms that I refuse to open here (but I hope that my argument is clear enough).
But we live in a universe that features consciousness. Since it is the only intrinsic nature we know of, panpsychists think that it is the best candidate to play that role. Combine this with the genetic argument and you get a rather elegant theory. However, Prof Pigliucci is sceptical: he’s not sure that any physicists would accept that they only study the structure of reality but not its content. But surely that is not a serious argument. To answer his question about what ‘structure’ and ‘content’ might mean, I suggest the following: ‘structure’ denotes the behaviour of elements in spacetime, how they relate, their position, etc.
For example, ‘an electron is a particle that flies around the nucleus’ (I know, I know: philosophers do not know anything about science) would be a purely structural description. That is, an electron is described solely in terms of what it does. The term ‘content’ might denote what that electron would be when isolated from all of the relations that it features in; what it is “in and of itself”, the ‘what-it-is-likeness’ of being an electron, etc. Certainly, a much more difficult example to give, but that is why consciousness comes in handy – it is the perfect example of what ‘content’ and ‘intrinsic nature’ might be. That is why panpsychists see it as such a strong candidate to play the intrinsic nature role. As for biology studying the content of consciousness – that just does not make sense to me. I am directly asking Prof Pigliucci here: in what way do biologist talk about consciousness that is not about its structure (i.e. about brains and the nervous system)?
Later on, Prof Pigliucci claims that there is no evidence that plants, bacteria, rocks, individual molecules of water, or atoms are conscious. As I have stated before, that is not what (most) panpsychists are claiming. We are not animists, who believe that rocks and rivers have a soul. Again, ontology might be sparse: only fundamental entities and beings we normally consider to be conscious – are conscious. As for there being no evidence that fundamental entities are conscious, the panpsychist might be sceptical of the proposal that attaining such evidence is even possible. According to many panpsychists, the theory is fully compatible with the general scientific worldview (including causal closure). We are merely redefining fundamental reality.
The world certainly will not start behaving differently once you accept panpsychism. That is, the fundamental entity was conscious all along – all of the behaviour that it usually displays is merely redefined as involving mentality. Let me illustrate this in a clearer way: a physicist who accepts panpsychism after many years would not start searching for evidence of consciousness at the fundamental level – they would merely realise that they have been observing what is consciousness-involving all along! No clash between panpsychism vs. science, theory vs. evidence, conscious vs. non-conscious, need ensue.
Prof Pigliucci also asks: Is consciousness a property of the quantum wave function? Can we carry out experiments to test this idea? The answer is no, it is not a property of the quantum wave function, at least not if it is supposed to be a relational (rather than intrinsic) property. The answer to the second question is also no: panpsychists claim that consciousness is an intrinsic and thus non-relational property, so it cannot (by definition) be experimented with or studied through an objective/relational/third-person approach. We are claiming that something exists in addition to the structural features studied by physics, so it would be odd to suggest that we can study it in the same manner in which we study structural features.
Near the end of his post, Prof Pigliucci criticises Prof Freya Mathews, an Australian philosopher working at La Trobe University. Her argument for panpsychism is that it is the only view that allows for a reanimation of matter in order to reconnect the subject with reality. It should be noted that Prof Mathews’ approach to panpsychism is very idiosyncratic. I believe she is making an ideological (rather than analytic) argument. That is, I think that she is claiming that panpsychism is preferable over physicalism and dualism because it is more useful and more potent as an environmental philosophy. While her views are certainly very interesting, meaningful and poetic, I do not think that she represents the majority of contemporary panpsychists.
Finally, Prof Pigliucci assesses the appeal of panpsychism: it allows us to feel at one with nature since consciousness is everywhere. This makes panpsychism seem like a New Age view to him. This is a very unfair characterisation. Most, if not all, panpsychists would strictly denounce the New Age movement. Its proponents usually accept theories and views because of personal or aesthetic reasons and are often disinterested in the arguments and the literature. Even if they are interested, more often than not they adopt a ‘know-it-all’ stance and define the arguments as they see fit, never really correctly engaging with the views and theories they hold dear. Contemporary panpsychists certainly do not fit the bill, nor do we discuss how to feel at one with nature, etc.
Okay, I am done. I wish to thank Dr Sabine Hossenfelder and Prof Massimo Pigliucci for discussing the matter with me on Twitter (see replies)! I also thank Prof Philip Goff (website and blog), my former supervisor, for joining the discussion, and my current supervisor, Prof Matthew Soteriou, for explaining the details of Nagel’s view to me!
David Chalmers – Panpsychism and Panprotopsychism.
David Chalmers – The Conscious Mind.
Frank Jackson – Epiphenomenal Qualia.
Freya Mathews – Panpsychism as Paradigm.
Giulio Tononi et al. – Integrated information theory.
Immanuel Kant – The Critique of Pure Reason.
Philip Goff – Consciousness and Fundamental Reality.
Philip Goff, William Seager and Sean Allen-Hermanson – Panpsychism.
Thomas Nagel – Mortal Questions.
Wikipedia – Vitalism.
William Seager – Consciousness, Information, and Panpsychism.