Your memories are almost certainly false

[disregardthat]

Of course we have no direct experience of reality. That is the modelling insight. But "entirely independent" and "utterly ignorant"? That is the quite unjustified next step.

We have patently improved our models of reality over time. And so the intelligent person moves on to talk about the epistemological basis of that improvement. Exploring modern modelling theory.

I'd say, applying concepts of our models of phenomena to noumena would be the unjustified step, for it generally makes no sense to say that we have a description of the structureless noumenal world. Structure is imposed, and that destroyes the possibility of having any meaningful scientific knowledge of the noumenal world. language is formed in relation to phenomena and phenomena only, and I don't see the reason to suggest that it in some way applies to noumena.

--------------------

I liked your post RexAllen.

It seems to me that the true fundamental facts are our observations, not physical facts per se. Physics is just a summary of human experience. We construct plausible scientific narratives that are consistent with what we observe, BUT these are descriptive metaphors, not explanations. Our observations are such that it is *as though* electrons exist...not that electrons *actually* exist.

What is meant by "actually existing"?
As phenomenal objects electrons do exist in the consistency of language in scientific models, but it would not make sense to call them "noumenal objects".

 

[RexAllen]

I liked your post RexAllen.

Excellent!

Sean Carroll's "From Eternity To Here", Pg. 182 (my comments follow the quote):

Cognitive Instability

I know from experience that not everyone is convinced by this argument. One stumbling block is the crucial assertion that what we start with is knowledge of our present macrostate, including some small-scale details about a photograph or a history book or a memory lurking in our brains. Although it seems like a fairly innocent assumption, we have an intuitive feeling that we don't know something only about the present; we *know* something about the past, because we see it, in a way that we don't see the future. Cosmology is a good example, just because the speed of light plays an important role, and we have a palpable sense of "looking at an event in the past." When we try to reconstruct the history of the universe it's tempting to look at (for example) the cosmic microwave background and say, "I can *see* what the universe was like almost 14 billion years ago; I don't have to appeal to any fancy Past Hypothesis to reason my way into drawing any conclusions."

That's not right. When we look at the cosmic microwave background (or light from any other distant source, or a photograph of any purported past event), we're not looking at the past. We're observing what certain photons are doing right here and now. When we scan our radio telescope across the sky and observe a bath of radiation at about 2.7 Kelvin that is very close to uniform in every direction, we've learned something about the radiation passing through our *present* location, which we then need to extrapolate backward to infer something about the past. It's conceivable that this uniform radiation came from a past that was actually highly non-uniform, but from which a set of finely tuned conspiracies between temperatures and Doppler shifts and gravitational effects produced a very smooth-looking set of photons arriving at us today. You may say that's very unlikely, but the time-reverse of that is exactly what we would expect if we took a typical microstate within our present macrostate and evolved it toward a Big Crunch. The truth is, we don't have any more direct empirical access to the past than we have to the future, unless we allow ourselves to assume a Past Hypothesis.

Indeed, the Past Hypothesis is more than just "allowed"; it's completely necessary, if we hope to tell a sensible story about the universe. Imagine that we simply refused to invoke such an idea and stuck solely with the data given to us by our current macrostate, including the state of our brains and our photographs and our history books. We would then predict with strong probability that the past as well as the future was a high-entropy state, and that all of the low-entropy features of our present condition arose as random fluctuations. That sounds bad enough, but the reality is worse. Under such circumstances, among the things that randomly fluctuated into existence are all of the pieces of information we traditionally use to justify our understanding of the laws of physics, or for that matter all of the mental states (or written-down arguments) we traditionally use to justify mathematics and logic and the scientific method. Such assumptions, in other words, give us absolutely no reason to believe that we have justified anything, including those assumptions themselves.

David Albert has referred to such a conundrum as *cognitive instability* - the condition that we face when a set of assumptions undermines the reasons we might have used to justify those very assumptions. It is a kind of helplessness that can't be escaped without reaching beyond the present moment. Without the Past Hypothesis, we simply can't tell any intelligible story about the world; so we seem to be stuck with it, or stuck with trying to find a theory that actually explains it.

So it seems to me that physicalism (the proposal that our experiences are "caused" by an independently existing material world) is riddled with "cognative instabilities". As is any theory that proposes a causal mechanism for conscious experience.

There is no sensible story to be told about existence.

Sean says: "Without the Past Hypothesis, we simply can't tell any intelligible story about the world"

I'd go further and say that even with the Past Hypothesis you can't tell any intelligible story about the world. We *can* say that the "big bang" theory is consistent with what we observe. But so is a higher-entropy past. And so is platonism. And so are a lot of things.

BUT these things all inevitably lead to more questions. There seem to be only two possible "final" answers:

1) Everything exists.

2) Reality is essentially arbitrary. There is no reason why existence is this way as opposed to some other way. It just is.

Note that option 1 can actually be collapsed into option 2: Why does everything exist? There is no reason, it just does.

Again, Kant's first antinomy:

“Suppose we were to accept the big bang hypothesis concerning the origin of the universe. Only a short-sighted person would think that we have then answered the question of how the world began. For what caused the bang? Any answer will suppose that something already existed. So the hypothesis cannot explain the origin of things. The quest for an origin leads us forever backwards into the past. But either it is unsatisfiable- in which case, how does cosmology explain the existence of the world? - or it comes to rest in the postulation of a causa sui - in which case, we have left the scientific question unanswered and taking refuge in theology. Science itself pushes us towards the antinomy, by forcing us always to the limits of nature.”

 

[RexAllen]

Never had too much love for Kant.

Why not?

Of course we have no direct experience of reality. That is the modelling insight. But "entirely independent" and "utterly ignorant"? That is the quite unjustified next step.

Where did Kant, Hume, and Berkeley go wrong then?

 

[apeiron]

BUT these things all inevitably lead to more questions. There seem to be only two possible "final" answers:

1) Everything exists.

2) Reality is essentially arbitrary. There is no reason why existence is this way as opposed to some other way. It just is.

Note that option 1 can actually be collapsed into option 2: Why does everything exist? There is no reason, it just does.

I don't think you are really focusing on what is being positively stated under this fluctuation hypothesis.

It says that "you and your world of experience, including all the logical notions with which you are constructing your current argument" are simply a "one instant" fleeting fluctuation. A random eruption of order that exists for about 10^30 seconds.

I am waiting for some further fleshing out of what actually does erupt into being? You mention that the eruption was within a thermal dust cloud. Well in what way could any arrangement of dust form a pattern in interaction? Dust is defined by its lack of interaction, except for gravity.

If you are claiming that just the right kind of atomic material erupts out of a quantum fluctuation to be a living, pumping, experiencing brain for a brief moment, then perhaps we can think of a brief flash of existence, before the poor Boltzmann brain gruesomely fails - boiling away in whatever vacuum it appeared in.

But you need to do more work pinning down what you are actually prepared to claim about the nature and duration of this fluctuation.

Before we are justified in rejecting reality, we would need a better fleshed out alternative.

 

[apeiron]

Why not?

Precisely because he argued in antinomies (incompatible dichotomies) whereas I side with the more ancient metaphysical principal that dichotomies are about fundamental compatibilities. Opposites make each other true (That is, A + not-A = everything that is possible concerning A).

Where did Kant, Hume, and Berkeley go wrong then?

Hume went right surely. Modelling is about models and measurements - having a causal model in your head, and then measuring the strength of its correlation with the world.

 

[Galteeth]

Again, the basis of the argument is that a microstates approach to modelling entropy cannot give you a global arrow of time. And that is really no surprise is it? The arrow is the emergent property of an entropy gradient. For a system at equilbrium, there is no gradient, and so no global macrostate change, and so no global property of "time" in a meaningful sense.

What Greene is arguing is that the Boltzmann ensemble model of entropy (and so interpretations of the second law made in those terms) only predicts what is the most probable state of a system - the maximum entropy of a system gone to general equilibrium. Now if we just take that statement in isolation, then we feel justified in saying that it is most probable that a systems is always at equilibrium. This in turn justifies us to say it is most probable that any system not yet at equilbrium is more likely to be a local fluctuation of some global state of equilibrium than that it is a global state of disequilbrium (lower entropy) still on its way to maximum entropy equilibrium.

What justifies all this is that no direction to time and change is wired into the Newtonian mechanical model of action. So even despite the observational evidence of everyday life and the big bang, we must look on this as most likely a story of local fluctuations from global equilibriums. Hence the Boltzmann brain if we just consider the occurrence of our conscious awareness. Or various cosmological views which see the whole big bang as such a local fluctuation.

There is certainly a problem here about how to explain the observation that the universe originated in a state of low entropy. But philosophically, the extrapolation of micro-physical models to arrive at patent paradoxes like "fake memories" is not really getting us anywhere (except to show that this line of thinking is indeed pathologically self-defeating).

The message really is that we should look to what the models are omitting, which again is the macro-physical features of reality. We observe gradients and an arrow of time (that is what the second law actually talks about) and so why not extrapolate from them?

That was well put, but I still don't quite understand what Greene's point is as you've described it.


Statement A: that the Boltzmann ensemble model of entropy (and so interpretations of the second law made in those terms) only predicts what is the most probable state of a system - the maximum entropy of a system gone to general equilibrium.


Statement B:
Now if we just take (Statement A) in isolation, then we feel justified in saying that it is most probable that a systems is always at equilibrium.

Why?

 

[apeiron]

Statement B:
Now if we just take (Statement A) in isolation, then we feel justified in saying that it is most probable that a systems is always at equilibrium.

Why?

It would always globally be at equilibrium, and locally open to producing negentropic fluctuations. If you take this line of argument.

 

[Galteeth]

It would always globally be at equilibrium, and locally open to producing negentropic fluctuations. If you take this line of argument.

Ok, I think I get it. And therefore a "big bang universe" fluctuation is less likely then a smaller fluctuation in which information creating an illusion of a universe with a consistent history has appeared. And that's where the paradox you referred to comes to mind.

Am I understanding this right?

Edit: Thinking about this, I am not sure there is a meaningful difference between the two, other then perhaps the "fake" universe might collapse into incoherency.


I mean this is sort of another version of the "deceiving demon" who produces a totally consistent reality who we can eliminate with ockham's razor.

 

[IcedEcliptic]

I know this is not the point being made, but memories are often added to, and not subtracted from. Eye witness accounts vary because of this, and other factors such as stress. Beyond that, Rex, your argument only makes sense in that when we die our memories are destroyed. Until then, we have a constant intake of energy to maintain the structures which contain them.

apeiron to me, seems to be having the right point in pure thermodynamic senses. I do not see why the reality we experience cannot be taken on its own terms, but that does not invalidate the totality of shared experience unless you are a Solopist.