Skip to contentWillowOne's Positions
TagsWhat’s newMediaStatistics
Search
Notes
WillowOne's Positions

Physicalism and Materialism

My Positions

  1. I am a physicalist. Everything that exists is physical, or is wholly fixed by the physical: once the physical facts are settled, every other fact is settled too. This is the position the rest of the vault rests on, and it is the one I hold against each of the alternatives written up beside it: Dualism, Idealism, Panpsychism, Neutral Monism and strong emergentism.
  2. "Physical" means whatever a completed physics describes, and whatever is built out of that. It does not mean "made of little hard bits". Materialism was the older name, and it was renamed for a reason: physics turned out to contain fields, forces, spacetime and probability amplitudes as well as matter, and a view that said "only matter" would have been refuted by the electron. I use the two words interchangeably in conversation and mean physicalism by both.
  3. I hold physicalism as a conclusion and not as a presupposition. It is the simplest model that fits everything observed so far, and it is held in the way everything else here is held (Fallibilism): until something turns up that it cannot accommodate. Nothing has.
  4. Physicalism does not say that the only true descriptions are in the language of physics. Chemistry, biology, psychology, economics and the sentence "I love you" are all descriptions of physical goings-on, at a level where the physics is invisible and the pattern is not. The physical basis of a thing does not exhaust what can be said about it, and "it is just chemicals" is true and uninteresting (Love).
  5. Applied to the mind, it says that mental states are physical states of a brain or are fully fixed by them, and that there is no experience without a physical system doing the experiencing (Consciousness, Mind-body dualism). Which physical systems can do it is a separate question (Substrate Independence).

Notes

  1. The case is an induction, and a long one. For four centuries, every phenomenon that was supposed to need something beyond the physical has turned out not to. Planetary motion needed angels until Newton; the diversity of life needed a designer until Darwin; living matter needed élan vital until biochemistry; disease needed demons and bad air until germs; thunder, epilepsy, dreams and visions each had a non-physical explanation and each lost it. The mind is the last large item on the list, and the pattern of the previous items is the strongest reason I have to expect it to go the same way. This is not a proof. It is the inference anyone would draw from a run of this length in any other subject.
  2. Causal closure. Every physical effect that has ever been traced has had a sufficient physical cause. Energy and momentum are conserved in the brain as everywhere else, to the precision anyone has measured. If something non-physical made a difference to what the brain does, there would be a place where the physics did not add up, and that place would be the most important discovery in the history of science. Nobody has found it, and nobody who believes in it is looking. Anything that makes no difference to the physics makes no difference to behaviour, speech, belief or this note, and I set it aside under Popper's Razor. The dualist who accepts closure and keeps the non-physical mind is left with epiphenomenalism, which has its own note and its own problems. This one argument does most of the work against every alternative on the list.
  3. The evidence from the brain is set out under Mind-body dualism and Souls and I will not repeat it, except to say what shape it has. Experience is altered by damage, drugs, development, disease, sleep and electrical stimulation, in ways that are specific, repeatable and increasingly predictable from the physical facts. It is built slowly by a developing brain and taken apart piece by piece by a degenerating one. A theory on which the mind is something other than the brain has to explain why it behaves in every tested respect as if it were the brain.
  4. What the alternatives have in common. Each of the rivals begins from the same observation, that it is hard to see how experience could be physical, and each builds an ontology to house the difficulty. Dualism adds a second substance or a second kind of property. Idealism makes mind the only substance and matter its appearance. Panpsychism puts a little experience into every particle. Neutral Monism posits a stuff that is neither and both. Strong emergentism keeps the physical and gives it powers that physics does not have. In each case the motivating step is the same: an inability to imagine how matter gives rise to experience, treated as evidence that it does not (Personal Incredulity, Owens Tryptic of Ignorance). Nobody can imagine how it arises from the alternative stuff either. The alternatives do not explain experience; they relocate it to somewhere it cannot be examined and call the relocation an explanation.
  5. The hard problem is not an objection to physicalism; it is a description of its unfinished business. David Chalmers' hard problem, Mary’s Room and the zombie are conceivability arguments: they ask what we can imagine and conclude from it what is possible. I can imagine water that is not H₂O; it does not follow that there could be any. What these arguments show is that "experience" and "neural process" are two concepts we have not yet connected, which is what one would expect at this point in the history of neuroscience. I expect the connection to be made the way the connection between "life" and "chemistry" was made: not by a single discovery that explains experience, but by a thousand findings after which the question "but why does it feel like anything?" stops being asked, because the person asking can see the answer being assembled.
  6. Reductive, non-reductive, eliminative. These are the in-house disputes. Identity theory says a pain is a brain state. Functionalism says it is whatever plays the pain role, in whatever it happens to be realised (Multiple realisability), and that is where I come down (Substrate Independence). Eliminative materialism, associated with Patricia Churchland, says the folk vocabulary of beliefs and desires will be replaced by a neuroscientific one as "humours" and "phlegm" were; I think much of the folk vocabulary will survive, because it tracks real patterns at the level where we live, but I hold that loosely. None of these disputes is a dispute about whether the physical is all there is. They are disputes about how best to talk about it.
  7. Hempel's dilemma. The standard objection runs: "physical" is defined either by current physics, in which case physicalism is probably false, since current physics is incomplete, or by some future completed physics, in which case it is empty, since nobody knows what that will contain. I take the second horn and deny that it is empty. "Physical" means the kind of thing that figures in the laws governing matter and energy, discovered by the methods that discovered the ones we have, continuous with them, and closed under causation. Whatever physics finds next will be physical in that sense. A disembodied mind, a god or an irreducible quale would not be, because each is defined by its not fitting into that structure. The boundary is drawn by method, not by inventory.
  8. "Physicalism is a faith too." It is not. A faith is a belief held in proportion to something other than its evidence (Faith). Physicalism is held in proportion to the longest unbroken inductive run in the history of inquiry, and I have said what would make me give it up: a physical effect without a sufficient physical cause, in the brain or anywhere else, replicated. Most of the alternatives have not said what would make them give theirs up, and that is the difference between a conclusion and a commitment.
  9. The lineage. Materialism is not a modern fashion. Democritus had atoms and void in the fifth century BC; Epicurus and Lucretius drew from them the conclusions I draw about death and the gods; Thomas Hobbes was a thoroughgoing materialist in the seventeenth century and was called an atheist for it. What has changed is not the thesis but the evidence, which has gone one way for two and a half thousand years.
  10. What it is not. Not scientism: the claim is about what exists, not about what is worth knowing or how to know it (World View). Not reductionism about meaning: see position 4. Not a denial that experience is real: experience is as real as anything, and physicalism is a claim about what it is made of, not a claim that it is not there. The physicalist who says "consciousness is an illusion" has, I think, said something misleading in order to say something true, namely that consciousness is not the kind of thing it presents itself as being (Daniel C. Dennett).

Sources

  • Stoljar, D., "Physicalism", Stanford Encyclopedia of Philosophy — https://plato.stanford.edu/entries/physicalism/
  • Papineau, D., Thinking about Consciousness (2002), appendix, "The History of the Completeness of Physics"
  • Dennett, D. C., Consciousness Explained (1991)
  • Churchland, P. S., Neurophilosophy: Toward a Unified Science of the Mind-Brain (1986)
  • Hempel, C., "Comments on Goodman's Ways of Worldmaking", Synthese 45 (1980), for the dilemma
  • Lucretius, De rerum natura, Book III, for the oldest surviving version of the argument from brain dependence

Also see