A criticism of supervenience-based physicalism

Pythagorean

thank you for using this format! It clears things up.

I think the issue is to what degree one accepts scientific realism, pertaining to your P2. Concepts are symbols for events in the real world. It's not a binary operator whether they fit or not. Some may be a good fit, others not so much. And it's not as if all concepts are lumped together. Some are more formidable than others.

That's not true. Pessimism is more a statement about human error and limitation:

"the aim of science is not to open the door to everlasting wisdom, but to set a limit on everlasting error" -Galileo

"Whether you can observe a thing or not depends on the theory which you use. It is the theory which decides what can be observed."
"Physical concepts are free creations of the human mind, and are not, however it may seem, uniquely determined by the external world." -Einstein

But some actually do reject physics logically, even thought hey contribute to it:

"I learned to distrust all physical concepts as the basis for a theory. Instead one should put one's trust in a mathematical scheme, even if the scheme does not appear at first sight to be connected with physics. One should concentrate on getting interesting mathematics." -Dirac

Maui

There is an example in my post - 'cats and dogs' decohering(splitting, emerging or whatever the current way of thinking is) from fields of possibilities. The physical basis of physical reality isn't physical in the traditional sense, so in a sense, everything appears emergent. Ask a physicalist how that happens, he will likely back off.

Ferris_bg

pftest, as I wrote before in this thread, supervenience does not entail emergence, which your examples illustrate. Supervenience is not emergence. They are not the same thing.

Maui

I am not sure why supervenience must be a conceptual relationship, why not just a relationship? Anyway, if i were trying to disprove physicalism or the idea of mind-independent reality, i'd use a simple twist of the double slit experiement - if an electron was emitted and there was a detector at only one of the slits and that detector detected nothing, because of complimentarity, we'd know with 100% certainty that the electron went through the other slit. Think about it - we detected nothing, disturbed nothing(no bouncing off a photon off an electron's wavefunction), yet the wavefunction collapsed. The only conclusion is that it collapsed because of our knowledge(and complementarity is preserved). 'Our knowledge' is the other name of mind, so if a physicalist wants to prove that a mind-independent reality ever existed, he has to embrace the relationship between matter/mind in this experiment(knowledge/detections). Most physicalists would either say that the universe could be participatory or that we shouldn't look at scales that small(as if it were somehow irrelevant )

apeiron

Even brains and minds are just concepts - enduring ideas formed by inference that we use organise our ever-shifting impressions.

So your P2 kills any kind of further discussion about anything stone dead. Unless you are going to defend something like "concepts about relationships can only originate and exist in the mind".

pftest

Spacetime didnt emerge in planets, it is distorted by planets. You could say the distortion emerged, but it would be weak emergence because spacetime is always distorted to some degree. And mass affects spacetime, but spacetime affects mass too.

Lets translate that to consciousness in the brain: consciousness didnt emerge in brains, it is distorted by them. It is influenced by and influences the brain.

pftest

All of physics is conceptual, but it is the physicalist position that there actually exists a physical world out there, that physics is our best bet as to what it is like, and that that bet entails an absence of any mentality in non-brains.

pftest

That decoherence actually sounds more like the opposite of emergence: first there are multiple possibilities, then some vanish and one is left. An interesting example to ponder on, and i think if it can happen, then the opposite (one possibility turning into multiple) is principally equivalent and should also be possible. Unfortunately im no QM expert so i am not yet convinced, but it is a challenge i cannot instantly dismiss.

I wonder what a "possibility" physically entails. Often when we say things disappear, they dont actually completely vanish, but they get changed to such a degree that they dont fit our arbitrary definition of the word anymore. In the wikipedia article, the introduction, it says that decoherence can be seen as information loss into the environment. If so, it would mean the "possibilities" dont actually vanish, but they leak away. That would argue against emergence.
http://en.wikipedia.org/wiki/Quantum_decoherence

pftest

Yes scientific realism seems to be the key here. Do not all physicalists, even when rejecting some or most of current physics (because humans err), think that there does exist a physical world, and that it was devoid of mentality until brains came about? My argument is that supervenience implies the presence of mentality, so a supervenient phenomenon cannot have come out of a situation devoid of mind.

pftest

Ok what i gather from the quote is that supervenience is a lawlike correlation. Saying that mind supervenes on brain doesnt say there is any kind of interaction or which came first, it merely says that there is a correlation between the two. And emergence is different because it says one phenomenon emerged out of the other.

Question: is there a difference between saying "mind supervenes on brain" and "brain supervenes on mind"?

Maui

I am not sure what you mean by "spacetime affects mass too", as spacetime in the current physics framework is is treated as geometry. Did you mean "different inertial frames(slices of spacetime) affect mass too"?



This could be, but there is no way to know. I am not sure that a simple logical argument can give any clue if this is so. As i pointed out earlier, that which can be known is the consistency of the model that physicalism proposes. If physicalism is wrong, consciousness would be anybody's guess and we'd have to start from scratch.

pftest

At the very least it influences the way mass moves, and it wouldnt be able to move at all without it.

The reason i mention examples like spacetime and the electrons in a skyscraper, is because they demonstrate how physical phenomena behave in nature. By looking at such examples, one can infer that physicalism is incompatible with physics.

Pythagorean

I think most empirical physicalists that are also pessimists are going to be closer to the horizon of new physics and new neuroscience because they're optimistic about overturning theories or discovering new ones. Lots of them will probably be right on the fringe, too.

Emergence and new physics/neuroscience are two contendors. Strong emergence would probably be considered a whole new paradigm to physics, but you could also have a reductoinist view of new physics.

On the other hand, weak emergence (a disclaimer: it's my personal stance to check my philosophical baggage) recognizes there are still undiscovered consequences of the fundamental laws of physics as they are; then you're allowing for nearly anything, but still sticking to the tried and true laws that have consistently been shown to hold in all cases that they've been tested in over many thousands of tests and many thousands of predictions.

The stance is that these new emergent properties will not somehow violate reductionist laws of physics and if they do, it's because of some specific exception or augmentation to the reductionist laws of physics that does not generally hold in all the systems it has been shown not to hold in.

But we additionally have the problem of confining our ideas and observations to semantic language and graphical spatial metaphors of data (plots) and contaminating it with purpose and meaning and antrhopomorphism and ahtropocentrism, which makes one more pessimistic. It also becomes more difficult to troubleshoot causality in large complex ensembles: "which ensemble of particles hit the other ensemble of particles first?"

However, the underlying philosophy is that we're still studying a consistent universe with a consistent set of laws: the laws of nature. And no matter how much we mess it up, once we get it right, and if we're able to sustain the information about it, our great great great great grandkids will still be able to demonstrate the observations themselves (if not take direct advantage of it through technology).