Are there thought experiments about physicalism?

Question

Other than Mary's Room and maybe Searle's Chinese Room are there any other interesting thought experiments against the ideas of physicalism, and the idea our minds are identical to our brains?

Answer 1

I think the idea of "arguing against physicalism" (or for that matter arguing for it) is basically misleading in a deep way, and is an attempt to do religion by philosophical means. Not that that is bad, but it is theology and needs to recognize that association. If you answered the question of the tenability of physicalism clearly and definitively in either direction, it would remain in some other form, ever-retreating and impossible to really address.

First of all, pro-mind, or even pro-quale arguments are not anti-physical arguments. One can accept physicalism and not believe the mind and the brain are identical. Richard Dawkins' notion of memetic ecology is clearly physicalist without dismissing the idea of mind or that minds contain language-borne ideas that have a life of their own and survive the death of the brain. Jung was alternately completely physicalist and an outright mystic, without contradicting himself. Tavistock psychoanalyts can accept the brain as physical and still see ideas unconsciously make their way from one person to another in a group, play out manipulations of the group mind and get resolved without ever being noticed, much less articulated, by the minds/brains processing them. So physical does not even rule out mysterious or spooky.

The mind can be an epiphenomenon of the brain and its network of interrelations with other brains without it ceasing to exist, and without all of philosophy collapsing into neurology. Just as atomism does not contradict our ability to make rigid structures, physicalism does not contradict our ability to discuss ideas that transcend individuals.

Second, to my mind, this is a clearly undecidable proposition. Given phenomena, you can either assume something or nothing is behind them. If we got behind them and discovered a basis, the 'nothing' camp would immediately simply add that basis to the list of things we consider physical, and, the end of time notwithstanding, the 'something' camp would still find unexplained phenomena.

We discovered electricity, something that exists in some weird distributed state that freely reaches across empty space, something as spectral as we could imagine in the 18th century, and when it stopped being entirely mysterious, instead of declaring there to be another layer of reality, we just decided it was physics. Then we discovered quantum mechanics, something that seems to strictly limit our ability to predict physical behavior, and instead of deciding we needed another name for this deeper level of causation, we devised wave functions and declared "the distribution of the possibility of the location of a particle in wave form", to be physics.

Our ability to declare things physical has no bounds. So like God and atheism, physicalism and non-physicalism are not a philosophically addressable questions, they are faiths. People who insist on deciding undecidable propositions have an agenda outside the truth. So, what is the agenda behind rejecting physicalism? Why put up with the question?

Third, we have already seen the 'synthetic' moment where this dichotomy ceases to be a useful guide. We got to Hegel, and the notion of human history as the attempt for the physical and the mental aspects of the universe to find common ground -- for matter (which is also God) to understand itself. So there is an 'agnostic' position here, we have middle ground, but we never walk over it. We keep the dichotomy clean, as though all intermediate positions are nonsense.

Finally, this argument tends to exist to eliminate other arguments, and that, to me, is an indicator of its ultimately destructive nature. If you decide something is or is not physical, you seem to have answered a question about what it actually is, an how it works. But you have not actually begun to try to do so. Once it is physical or non-physical, depending upon who you are, you can relegate it to some science or to some religious position, and stop considering it philosophically until that science or that palliative framing gets to some unresolvable question. But that is just laziness. There is no reason only quantum mechanics seems philosophical to us, and not field theory, or thermodynamics. We just don't like the fact that those other sciences have huge historical weight, and a lot of facts in them.

Answer 2

I was surprised to learn that this one (from the "Related" sidebar), regarding philosophical zombies, is actually used in published philosophical works as a refutation of physicalism (David Chalmers is a name mentioned there).

My dismissal of it would be that claiming, "Zombies are physically identical to us but lack consciousness, therefore physicalism is false," is an extremely blatant form of circular reasoning -- the assertion that consciousness is not physical is implicit in the assertion that zombies are physically identical to conscious human beings but do not possess consciousness. The claim might as well read, "Consciousness is not physical, therefore physicalism is false". No thought experiment required!

I think p-zombies are a great concept for other reasons ;) But if they exist, their defining characteristic would be that they are indistinguishable from normal people but lack consciousness. That we would consider them indistinguishable from us does not equate to them being physically identical, even if we could not identify the difference with our fine tooth combs.