And why would anyone decide that some of our experiences are not actually being experienced? Because it doesn't fit well with their ontology. So Dennett has to say that we are all p-zombies. There are only objective experiences.

What about when we dream of seeing red? Well, we don't actually dream, we just seem to remember to have dreamed. Those are the contortions one has to make to consistently deny subjective experience.

But the advantage is that it makes the hard problem go away for Dennett, and he gets to be on the side of science, while Chalmers, etc are mysterians and woo mongerers. And by Dennett, I mean anyone who argues along these lines.

No I am saying it is not possible to abstract anything from elusive subjective access. — m-theory

Interestingly enough, the idealists, at least some of them, might agree with this. Didn't Berkley argue against abstacta?

But I don't agree, so I might agree that some of our experience is objective. So let's say that Locke was basically right and shape, number, extension, etc are objective features of physical objects.

So that's great, we can do science and believe that it truly attempts to describe the world as it is. But what about when we want to explain the rest of our experiences?

Do we draw a line in the sand and deny that color, sounds, smells, etc are really being experienced?

If we can do that, then why stop there? What makes the objective world that we experience any more real? Why not deny that we experience shape, number, etc?

It potentially undermines itself, or at the very least, is inconsistent. What is being done is deciding that certain experiences are real, and the rest are not even experienced.

If you are not then you have no well formed logical method to define self. — m-theory

My world is my self? Yeah, I identify my own self as this body amongst other bodies and objects, but it's not the only way to think about the self. I could identify self with the summation of my experiences.

Isn't mysticism and Eastern religions about overcoming the illusion of self and seeing that all is one, and all that jazz?

Subjectivity is abstracted from a necessary objectively existent dichotomy. — m-theory

You're saying because of the other who has their own experiences, I know that mine are subjective, so it's the objective existence of other experiences which justifies my own subjective experience.

I don't think idealists would agree with that, but not a bad attempt.

As sure as you are that there is self, you are necessarily just as sure that there is a not self. — m-theory

I'm not, because solipsism retains it's logical irrefutability under the right formulation, even if I don't find it compelling.

To doubt entails that something must that doubts. — m-theory

Alrighty then, to ask whether subjective experience exists entails that something which experiences subjectivity exists.

It's not quite as straightforward, because you need to also show that objectivity is abstracted from subjective experience, such that arguing objectively for subjectivity is to assume subjectivity in the first place.

IOW, doubting subjectivity undermines the objective. This is something that Dennett, etc seem to not realize, but probably they would not accept the premise that subjectivity is necessarily the starting point.

So maybe more argument is needed here. For me, it's enough to note that you don't have my experiences, and I don't have yours, and the only way we know about the objective world is via our own experiences.

If I am certain that you exist, it is because there is an effective procedure such that it is not logically possible to doubt that you exist. — m-theory

I am not certain that you exist, I'm just confident beyond reasonable doubt. I am certain of my own existence, whatever that entails (brain in vat, Neo, demonic dream character).

But like I said there is no reason to assume that there can be no full or complete account, or rather it is not logically necessary to assume this. — m-theory

The arguments against physicalism qua qualia is that no physical theory has the structure needed to explain consciousness.

David Chalmers, Colin McGinn and Ned Block have argued along those lines. Chalmers argument is that structure and function do not account for experience. Ned Block's argument is that the view from nowhere, or objectivity, cannot account for a view from somewhere or subjectivity.

The Lockean way of thinking about it is that we abstract from subjective qualities to arrive at the objective ones, and then we try to justify just the ontology of the objective ones by explaining the subjective ones in objective terms. But this is impossible.

It would be like coming up with a mathematical equation for the experience of red. Math isn't something that captures experience. It's an entirely abstract language.

I guess philosophy is just silly that way! — m-theory

These sort of questions are silly. You don't need to argue that you exist. Descartes only got to that point because he was trapped in doubting everything else and needed an out.

Again how do you know you are having them?
How can you be sure? — m-theory

How do I know I exist? How can I be sure?

Descartes has already demonstrated that there is a logical method for being sure you exist. — m-theory

How do I know that I think? What makes thinking any different than experience with existential questions?

I experience therefore I am. That's just as good.

Yes that does not address the issue of your knowledge of mental phenomena that simply are.
How to you know they simply are? — m-theory

Because I have them, just the same way I know that I exist, because I exist. Granted, I have to the kind of animal that is self-aware to do that. You might ask me to logically argue for being self-aware. But that would be silly.

My entire point here is that physicalist do have an account for mental phenomena, and that the skeptics can disagree with that account to be sure, but what they would be in error if they said that mental phenomena is inexpiable for the physicalist and the physicalist has no account for them. — m-theory

That certain neural activity is the cause of consciousness? The problem here is:

1. Distinguishing this from correlation

2. Showing how certain neural patterns implement consciousness (and why others don't), and whether that can be reproduced in other media, and to what extent other things or animals are conscious.

3. Determining the exact nature of consciousness.

So with water we understand the properties to be due to the chemical nature of H20 when those molecules combine together. We don't have that sort of thing for consciousness. We don't even know what it is. An electrical pattern? Information? A network? Algorithms implemented by the brain? Does it extend out into the body? Is it interaction with the environment?

Otherwise, we're just noting that certain regions of the brain light up under fRMI, or if you're brain damaged in a certain way, you lose consciousness, or whatever.

So you need a chemistry or some science of consciousness that answers the various questions. What is bat experience, if it has experiences? Can a machine be conscious? How did it evolve, etc.

Then you cannot actually claim you are logically certain you are having them. — m-theory

Wouldn't the same principle apply to my existence? Am I supposed to provide a logical argument for existing? Isn't it just the fact that I exist?

My existence is a starting point or arguing. Maybe I try to argue that I exist because God, or evolution, or aliens. But that I exist is brute in that I can't argue for or against it.

Pencil and paper can't get you a cup of "Earl Grey Tea, Hot!" or play Chopin, or win against you in a Chess match, et cetera. Pencil and paper can't even read itself. — Nils Loc

Ture, but then neither can software. You have to have peripheral devices hooked up to your computer to do all that.

hat makes experiences of color etc. obtain is that those are properties of matter/structure/process complexes. You need the right sort of matter, in the right structures, undergoing the right processes, or you don't have the properties in question. — Terrapin Station

So you subscribe to an identity theory of mind. The physical substrate is necessary for conscious experience. Has to be squishy meat.

1.216 billion. See, they could do it too. — mcdoodle

I was imprecise. Most experts agree that 1.378 billion humans is needed to implement a universal Turing machine.

A lot less Datas would be needed, though. Only about 575 Datas could emulate their dreams on paper.

I don't follow sorry. — m-theory

An idealist could ask whether material existence is determinable by logical argument, or just something the physicalist begins with as a premise.

Or it is possible that there is some logical method for determining your experiences, but it is simply not within your subjective awareness, and thus seems to be brute when in fact it would be an effective logical method. — m-theory

There is a logical argument for determining the nature and cause of my experiences, which could be physical. A physical correlation has been established, to the extent one accepts physicalism on ontological grounds (which I'm fine with btw).

But there is no logical argument for the raw fact that you have experiences. You just have them, and then at some point, encounter different arguments for why and what they are. And then maybe make your own version of them.

Experience is a priori to any argument.

So you don't use logic to know if you have experiences or not? — m-theory

No, do you? How does that work? You form an argument and then experiences pop out with the conclusion? I'm curious, do you experience forming this argument?

So there is no logical method for deciding if you do or do not have mental phenomena? — m-theory

There's a logical argument for what constitutes mental phenomena, but that I experience seeing red, etc is not an argument.

Irrelevant cultural side note: Why do we assign these mind numbing tasks to a billion Chinese? Do we suppose they have nothing better to do with their time. Why not a billion Africans? A billion Europeans and North Americans? Isn't it enough that they have to make all this junk we buy, without having to do all this calculation on top of everything else? — Bitter Crank

Because racism. Only a Chinese substrate will realize a true Turing machine. God is Chinese, and Searles messed up by having the room output Chinese, otherwise he had a solid argument. Silly Searle.

But really, probably because China is known for having more than a billion people. India would have worked. Africa is just too general. I don't even know how many people live on the continent, and I'm pretty sure there aren't 1 billion Europeans.

Why 1 billion? Because it's nice big number, but not too big for there to be that many people. So now you know!

All universal computers are equivalent. What you need to argue is that a billion Chinese human computers, cranking out an algorithm, constitutes a computationally universal system which is realisable. — tom

Humans were computers before electronic computers existed. Is there a reason why enough humans given enough time can't compute any algorithm? How is that different from a turing machine with infinite tape?

Why not just program qualia on your laptop? — tom

Does anyone have any idea what sort of algorithm that would be? The point is to ask what it is about algorithms which could lead to experience.

You can take this as a criticism either against the computational theory of mind, or a criticism against universal computation (the substrate doesn't matter).

The OP question is, of course, a variant of the Chinese Room problem. — SophistiCat

It is except the focus is own conscious experience and not understanding. Arguably, a fair amount of progress has been made in computer understanding with machine translation, image recognition, search algorithms, etc. But no progress whatsoever, far as anyone can tell, has been made on experience.

Also, I'm delighted that you used pencil and paper, which I think is still the greatest technological innovation that our species has accomplished. — andrewk

Interesting. Why that one in your opinion over fire, clothing, or the printing press?

You can conjecture that decisions about the existence of intentional states and/or experiences is undecidable from current understandings in logic, sure.
It is probably more interesting than the physicalist position, sure.
But it certainly isn't logically necessary to speculate thus, at least not at this point. — m-theory

The same sort of thing could be said of external objects. An idealist could turn your argument on it's head and claim that material objects are undecidable for the physicalist.

If they are not decidable that poses problems for physicalism sure, it would mean that we cannot logically determine if we experience intentional states. — m-theory

I disagree that this something to be logically determined. My experiences would be the premises one starts with to make a logical argument. It's not something to be argued for. There is no line of reasoning I follow to logically determine that I see red. I just see red and am aware of it. That's where logical argument can begin, but not before then.

I don't need to determine that I have experiences. I have experiences, period. What do those experiences amount to (or what is their origin and nature)? That's something which can possibly be determined by logical argument, but not that I have them.

Now whether you have experiences which I don't have (as an extension of my experiences) is something which can and has been argued ad nauseam. But notice that the solipsist need not and cannot make an argument for their own experiences. They just are. It's brute.

All logical argument has to start somewhere.

Note that if mental phenomena and intentional states are undecidable then there is no method for concluding that those phenomena or states exist. — m-theory

You mean there is no objective method. Subjectively, I know that mental phenomena exist, because I experience it. That's how I can know with certainty that nobody else can be a solipsist, to the extent one takes solipsism seriously.

That is to say if you can be sure that you have mental phenomena there must be some effective mechanical procedure for arriving at that conclusion without error. — m-theory

You mean to be sure other people have mental content? Because again, I experience my thoughts, my perspective, my dreams, etc. Whatever mental content are, I have them, and I cannot doubt that I have these experiences, however one wishes to categorize them.

However no such breakthrough has been discovered so, philosophically, physicalist proceed with what we can know based on current methods. — m-theory

You mean what can be objectively known. Here is a potential problem for physicalism. It beings with objectivity, which means factoring out our individual subjective experiences. This works great for science. But it has the one big problem of turning around and explaining subjectivity, because at the start, subjectivity was removed.

In Lockean terms, you get rind of color, sounds, smells, etc to explain the world in terms of number, shape, extension, etc. That's great until you need to account for our having colors, smells, etc.

How does one derive smell from number? Is there a mathematical equation for experience? Do you now what sort of algorithm would enable a machine to experience the sweet smell of rose?

I think intentionality can be exhibited by mindless objects: robots, computer programs, animals. This in a way solves the problem of intentionality at a stroke. The big problem remains however - that of the quale of intentionality. — tom

Why group animals with robots and computer programs? Animals have nervous systems, and they have their own goals independent of us (often enough at odds with us). Computer programs and robots just do what we design or program them to do. As such, attributing intentionality to them could just be a case of anthropomorphism. Seeing intentionality in things that lack it because they have a behavior or look familiar to us. It's like seeing shapes in clouds or thinking the volcano god is angry.

For those who like the pilot wave theories: — Agustino

Actually, that video was pretty amazing! Maybe there really is something to pilot waves. I didn't know there was a classical system that produced similar results for the double slit experiment. And you can see it happening! Definitely helps visualize de Broglie's interpretation.

I guess the bouncing silicon oil drops creating the standing waves is a classical pilot wave system.

Yes we do — tom

Feynman said that nobody understands, assuming that wasn't taken out of context, but I always understood him to be saying that nobody knows why the double slit and other experiments give the results they do. How many nuances to the various interpretations are there, btw?

For systems of more than one particle, QM takes place explicitly in Hilbert space - not in the space-time. — tom

What is Hilbert space, and what makes it any more real than probability waves? And I don't mean what is the math, I mean what does the math represent?

I am sympathetic to everything you report him as saying there, and it's a widely held interpretation. — andrewk

I didn't explain what I heard well. It was only after several pages of replies that I figured out how to express it clearly.

That is why, I think, it is 'rate independent' - the 'wave pattern' really is embedded in the fabric of reality itself, it is of a different order to the physical. That is why the 'nature of the wave function' is the metaphysical question par excellence. — Wayfarer

This is where I get confused about the Copenhagen interpretation. Is it anti-realist, or is it saying that reality is this non-classical stuff of possibilities that behave like a wave? That seems to be two different interpretations.

The first one leaves questions unanswered. It's the sort of thing Landru of the old forum would have been happy to endorse. Our experiences have a structure. We don't know why, but realism just presents a regress, etc. In terms of the double slit experiment, we don't know why it results in an interference pattern when there isn't a detector on one of the slits. That's just what happens, and physicists developed the math to describe/predict it, because science is merely concerned with prediction (on Landru's account of it).

While the second one, that the world is actually made of probability waves until a measurement (or decoherence) takes place, is puzzling, weird, and almost mystical. The second one is making an ontological claim.

Einstein asked the rhetorical question 'does the moon still exist when nobody is looking at it?' — Wayfarer

It's gravity certainly does. The unobserved particles have properties that are important to atomic structure and fields of force. It's similar to noting that the floor keeps holding you up even when you don't notice it. Somehow the stuff of everyday life is held together despite not observing all the particles making it up.

One of Bohr's quotes is 'that there is no particle prior to the act of measurement'; which is why Einstein asked the rhetorical question 'does the moon still exist when nobody is looking at it?' — Wayfarer

Let's say Bohr was right. Why the interference pattern, then? Why not some other probability distribution? It's highly suggestive that something is interfering. After all, that's what observable waves do.

And science has a track record of positing what are initially unobservables, and then coming up with instruments to make those observations. At one time, atoms were just theoretical posits. Anti-realists could have (and maybe did) argue that they were useful fictions for making sense of experiments at the time. But now we can observe them, so obviously they are more than useful fictions.

o it would appear that the people involved are debating interpretations and not challenging the postulates of QM, or deductions therefrom like the Heisenberg Uncertainty Relation, which would have been a worry. — andrewk

Yes and no. I'm pretty sure Binney challenged taking the postulates of QM literally (realistically), when interpreting the results. He said they were very useful tools, but the Schrodinger Equation, for example, has unreal properties (such as leading to a superposition of states). He also mentioned the Heisenberg Uncertainty Relation, and I'm pretty sure his interpretation is at odds with taking that realistically, since he thinks probability is epistemic, and not fundamental. Thus, a measuring device has an exact quantum state (state that all the particles and molecules are in), and not a wavefunction.

Just to pick up one of the possible meanings, if 'uncertainty' refers to the probabilistic nature of the value obtained from the measurement, as assessed prior to the measurement, and based only on information about the observed system and not the measurement apparatus, then that agrees with the Decoherence theory, which is widely accepted. If that's what was meant then the prof is not saying anything controversial, or new, at all — andrewk

No, that's not what he was arguing for. Binney stated several times that the probabilistic nature of the value obtained was due to our epistemic uncertainty about the exact quantum state of the measuring device, and not anything fundamental about the state of the particle prior to being measured. A little reading up on HMI reveals that this particular interpretation understands probability to be entirely epistemic (our ignorance or inability to measure everything accurately) and not ontological or fundamental.

My understanding is that decoherence has to do with normal macroscale objects, such as detectors, interacting with isolated quantum systems, which are fundamentally probabilistic, or at least the math describes those systems as being so, causing them to lose their coherence, leaking the quantum information out into the wider environment.

But it doesn't do away with superposition. In the cat thought experiment, although it explains why we don't see both a live and dead cat when opening the box, it doesn't explain what happens to us and the rest of the universe. That still requires an interpretation, and I believe MWI is compatible with decoherence.

ou're right that there's no need for it in the context of a discussion about the 'measurement problem' (which I'm guessing this thread is somewhat related to, but I'm still very unsure of that), — andrewk

At the beginning of the talk I linked to, Alan Bar introduced the measurement problem for the audience, then Simon Saunders argued for MWI, followed by James Binney discussing HMI, I guess, although he didn't give his interpretation a name. The Youtube title is: "The 1st Ockham Debate - The Problem of Quantum Measurement - 13th May 2013".

There are no particles as such prior to the act of measurement. Literally all there is is the possibility of there being one. — Wayfarer

I don't know what that means, though, unless one is an anti-realist, which I'm not.

It is the measurement which reduces the probability to actuality. — Wayfarer

But how do you go from probability to actuality? What is the mechanism? Is this just brute?

That is not historically accurate, and you really need to stop pretending quantum mechanics is a "model", it's not, it's a theory i.e. a statement about what exists in reality, how it behaves and why. — tom

Alright point taken, but the question is whether the Schrödinger equation is describing the real state of the particle before it's measured, or it just has predictive power as a useful tool, and the reality is something else. Afterall, what the hell is a probability wave supposed to be?

In context of Binney and HMI, if the reality would be our epistemic uncertainty about the complex state of the measuring device having a large influence on the particle it's detecting.

If MWI is the case, then probability wave is a description of other worlds. Or it could be pilot waves guiding the particle. But then again, perhaps reality is a jumble of possibilities when we're not looking? Question is why does measurement make it classical? Why is our lived experience mostly classical?

so far as as the"measuring device" is concerned, and I'm quite surprised that Binney does not recognize it, exactly what are the boundaries to the "measurement device" and how do you ever establish its state if it is constantly changing? — Rich

That is a big problem. Perhaps as big as not being able to detect other worlds or pilot waves.

However, for science the math is what counts — Rich

Science isn't math though. It's an empirical investigation of the various phenomena in the world. As such, the world has the final say, not math. Experiments and observation are what ultimately drive the math.