Sorry about the delay! Hopefully you’re still around an I’m not posting stuff to myself.

Would you agree that changes in physical reality can produce changes in conscious experience, and in this sense can “meaningfully explain conscious experience”?

No. Though I will agree that this is the most obvious interpretation of what we observe. If you don’t give it much thought, that’s probably what you’ll come up with. Simple, easy to grasp, and wrong.

That said, the best argument I know for pursuing an explanation is that our consciousness is embodied; physical changes to our bodies can and often do affect our subjective experience.

My point is that there can’t be any “absolute” explanations for anything if the material universe exists uncaused. The uncaused nature of it’s existence is transmitted to all of it’s contents. Everything that follows from an uncaused beginning is ultimately uncaused as well. If the universe exists uncaused (or as a result of some other uncaused event), then reality just is what it is. Reality is tautologous.

Okay. Bear with me here, I’m going to tie this back to your post:

So, let’s say your wife’s car won’t start and you explain to her that it’s because the car is out of gas. This an operational explanation. In the context of the situation, it is meaningful. It is meaningful to you, it is meaningful to her. It has subjective meaning.

But it is not the end of the matter. It’s not an absolute explanation. Absolute explanations
account for *everything*, the entire ontological stack of what exists.

So, why did the car run out of gas? Well, maybe she forgot to fill it up. Or maybe there’s a leak in the fuel line. Or maybe somebody siphoned the gas out of the tank. And of course, none of those are the end of the matter either, as each one has it’s own causal precedents.

But let’s just go with “she forgot to fill it up”. Why did this happen? Well, there there are probably many reasons that contributed to her forgetting, not just one reason. It’s not a single file line of causes, but a whole causal web. But the chain metaphor still works because the web is a directed acyclic graph whose nodes can be divided into layers, with each layer viewed as a link in the chain. So there are two options as to what we find at as we trace back along this causal chain: we have an infinite past and never reach a beginning, OR there is eventually a first cause where the universe comes into existence. For now let’s assume that if you trace back far enough, there was a first cause…which itself was uncaused.

Okay, two scenarios:

1) Physicalism is true, you’re in the real world, and your wife ran out of gas.

2) Physicalism is true, you’re in a computer simulation of the real world, and your virtual-wife ran out of virtual-gas.

SO, in both scenarios, your operational explanation that she ran out of gas is useful, and applies equally well. It has subjective meaning. BUT, it has no absolute meaning. If it had absolute meaning, then it wouldn’t apply to both scenario 1 and scenario 2.

My point in my previous posts is that there IS NO absolute meaning. And where there is no meaning, there can be no explanation. In an absolute sense, things just are what they are. Tautology.

So QM is a theoretical framework that is consistent with our observations. As such, it has subjective meaning, since observations are subjective.

Anywhere you subjectively make the same types of observations that you make here on “real earth”, then QM will be a good framework to use when attempting to anticipate future events. Even if you are *really* in a computer simulation.

For example, the random decay of unstable nuclei.

What are unstable nuclei? They are nuclei that have lower energy configurations that they can relatively easily be jostled into. Why are those other configurations lower energy? Why the relative ease of jostling? Why does there exist a phenomenon capable of jostling in the right way? Because that’s the way things work in this universe.

But if the laws of physics were different, then what we observed would be different. If physicalism is true, maybe there are yet other universes with different physical laws out there where all nuclei are stable. Unstable nuclei just cannot form under those alternate laws. String theory landscape, false vacua, that sort of thing. Seems possible, right?

The existence of unstable nuclei is consistent with our observations. Even if they don’t actually exist, using them as theoretical constructs makes sense when thinking in terms of QM, which we ultimately only bother to do because it makes useful predictions. It’s useful. Even if we were actually in a computer simulation being run on an alien computer in an alternate universe whose physical laws didn’t produce unstable nuclei – STILL, for our subjective purposes inside the simulation, we would want to talk about unstable nuclei, because they fit our simulated observations, and it’s easier to think in terms of unstable nuclei rather than in terms of mathematical equations which could be interpreted as such.

Okay, so here’s my view of the situation:

1) Physicalism has an explanatory gap between matter and consciousness.

2) All causal explanations of consciousness ultimately lead to uncaused origins

3) Uncaused things cannot have meaning or explanations in an absolute sense

4) Things which follow entirely from uncaused beginnings are themselves ultimately uncaused

5) Therefore, one way or another, directly or indirectly, consciousness is uncaused.

6) Given the choice between directly uncaused or indirectly uncaused, I’ll take directly uncaused, as there’s no practical difference between the two.

7) There is no explanation for what we experience. Reality just is what it is. Reality is tautological.

8| Science is about what we observe, not about what really exists.

Did you take a look at the Chalmers paper? Actually, currently his site is down. Might try it here. Or just google for “Facing Up to the Problem of Consciousness”. I’m sure there are copies scattered about on the interweb.

Section 2 is pretty short and does as good a job as anything I’ve seen of explaining the issue.

The Kazanas paper was one of several (also one by Starobinsky and one by Sato, off the top of my head) to suggest somewhat inflation-like scenarios. Guth’s paper was the one that really put it all together and showed how it could solve several cosmological problems.

Usually interesting scientific discoveries come about gradually through the work of many people, but unless you want every discussion of the subject to include a lengthy disquisition on the entire historical path, it’s convenient shorthand to name the person who really got it right rather than all of their predecessors. (In a history discussion, rather than a physics discussion, greater care is obviously called for.)

Sean : a couple of historical question/nitpicks
AFAIK, the formula for black-hole entropy was first given by Bekenstein(whereas you mentioned Hawking in your discussion) ?
Also another question. Would you consider this model (proposed in 1980) as a generic model of inflation? (of course it was not called inflation)

Sometimes I suspect that what I think of as my conscious experience is somehow radically different from what other people are talking about when they talk about conscious experience – I don’t see any difficulty with physicalism (assuming you include information processing in the realm of physicalism) explaining conscious experience. I certainly can see the evolutionary advantages of consciousness, especially for a species that relies on cooperative hunting. One of the things that hunters do is to project themselves into different positions and circumstances relative to the prey. Hunters also project themselves into the role of the prey in order to get an idea of what the prey can sense. This projection of a sense of ‘I’ relies on there being an internal sense of ‘I’ – consciousness. I’ve watched cats (domestic) hunt, and while they have great hunting instincts and reflexes, I’ve never have seen any behavior that would indicate that they use this type of conscious for their hunts.

I’m not suggesting that consciousness necessarily evolved for the purpose of hunting – it may have evolved for other reasons and then it just turned out to be useful for hunting.

I realize that some people may not agree that known correlations between the states of our bodies, in particular our brains, and the content of our conscious awareness constitute any sort of meaningful explanation. That said, the best argument I know for pursuing an explanation is that our consciousness is embodied; physical changes to our bodies can and often do affect our subjective experience. It is a commonplace fact that physical events can alter or deprive us of our consciousness, often without killing us. Indeed, from the perspective of human biology and medicine, our state of consciousness is as much a property of the living organism as our ordinary vital signs. The key motivation for attempts at any physical explanation is the existence of stable structure and correlated change in the world, whether one is considering astrophysical systems and their dynamics, or terrestrial biology and its dynamics.

The Many Worlds interpretation of QM is fully deterministic, right? As is the de Broglie-Bohm theory, and I believe t’Hooft has proposed a fully deterministic theory as well. Determinism is by no means dead.

Also I think you’re also premature in your claim that a timeless view of the universe is obsolete. See Julian Barbour’s work for instance.

Further, the problem isn’t really determinism vs. indeterminism. It’s bottom-up causality vs. downwards causation. If physics implies that reality (including conscious experience) can be reduced to and explained in terms of fundamental physical entities (particles, fields, strings, whatever) plus the laws governing their interactions and behavior (regardless of whether these laws are deterministic or not), then my point is valid.

So I said: “Well, it would seem that you are saying that the initial state of the universe, plus the laws of physics as applied over 14 billion years or so determines their state of mind, right?”

I never said that these physical laws were deterministic. Only that they determine your conscious experience. And it was explicitly in my thoughts that they might not be deterministic when I wrote that. As an example: Your decisions can be determined by a roll of the dice or by careful analysis…use of the term “determined” is still appropriate in either case.

But ultimately it doesn’t matter. If anything, quantum indeterminism works in favor of my view, not against it. If physical reality is rife with uncaused inexplicable events, then it seems to me that just further undermines the claim that it can still be used to meaningfully explain conscious experience.

That isn’t even approximately the point I was trying to make. I’ll have to save a fuller explanation for later. For now, I’ll just say this: I wish you would stop harping, as you appear to be doing, on a strict determinism of states in the present by the past history of the universe.

As I already emphasized in my comment #11, that idea is no longer tenable. It is not clear exactly what sort of worldview should replace it, but quantum mechanics, and for that matter non-linear dynamics, make quite clear that something else is needed.

If the atoms and electrons that make up their brains were stacked one way, they would agree with me. If the atoms and electrons of their brains were stacked slightly different, they would disagree with me.

But what determines the arrangement of these particles, in your view? Well, it would seem that you are saying that the initial state of the universe, plus the laws of physics as applied over 14 billion years or so determines their state of mind, right?

And what determined the initial state of the universe, plus the laws of physics? Well, either the universe exists uncaused, OR it is caused by some pre-existing reality…which itself is uncaused. That’s your alternative?

Again, I don’t see a major difference in terms of plausibility. Either way, our conscious experiences are ultimately uncaused. You seem to draw some sort of comfort pushing this inconvenient fact back in time (whatever time is) to the distant past. But this is just a change in perspective, not a real change in what is.

So there is some similarity between my position and Berkeley’s idealism, but my interest in the topic was sparked by David Chalmer’s Facing Up to the Problem of Consciousness.

So there’s no doubt in my mind that human ability and behavior can be explained *in terms of* mechanistic physical processes. But, this still leaves the question of conscious experience. As Chalmers states in his paper:

“Why is it that when our cognitive systems engage in visual and auditory information-processing, we have visual or auditory experience: the quality of deep blue, the sensation of middle C? How can we explain why there is something it is like to entertain a mental image, or to experience an emotion? It is widely agreed that experience arises from a physical basis, but we have no good explanation of why and how it so arises. Why should physical processing give rise to a rich inner life at all? It seems objectively unreasonable that it should, and yet it does.”

So obviously functionalism, and particularly computationalism, seems like the logical starting point for physicalists in explaining consciousness. And functionalism/computationalism implies multiple realizability – If the causal patterns of neural organization were duplicated in silicon, for example, with a silicon chip for every neuron and the same patterns of interaction, then the same experiences would arise. And obviously it’s a short step from here to the “simulation argument.”

The causal structure of my computer is vastly different than that of my brain, but in theory it would seem that my computer should (eventually) be able to perform the same type of information processing (computationally) that my brain does.

But, if you think about it, this leads to a further set of questions, in that if conscious experience is produced by “computation”, what exactly is computation? And when can a physical system be said to implement a particular computation? Hilary Putnam and John Searle have both formulated attacks on this line of thought, basically making the argument that computation is ubiquitous…every physical system can be interpreted as performing nearly any set of computations.

So, I won’t go into the details now, but ultimately after working through all the twists and turns, I’ve come to the conclusion that conscious experience must itself be fundamental, and not a mere side-effect of quarks and electrons going about their business in an uncaused universe.