Re: subjective reality

From: Bruno Marchal <>
Date: Fri, 19 Aug 2005 11:48:06 +0200

Hi Godfrey,

Le 18-août-05, à 20:27, a écrit :

> [BM]
> OK. Now I agree with Lee, and many on the FOR and the Everything
> lists that Everett (many-worlds + decoherence already) constitutes a
> "solution of the measurement problem". All measurements are just
> interaction, and then all states are relative. As I said, it seems to
> me that this is even more clear in the integral formulation of QM
> where F = ma can be deduced from the "sum on all histories". But this
> is going a little bit out of topics, and is not needed to understand
> the comp derivation. We can come back on this latter.
> [GK]
> Here we part company. MWI (I prefer to call it Everett's
> Interpretation or EQM) is NOT a solution to the measurement
> problem of QM but an Interpretation of Quantum Mechanics that does
> not lead to that problem! It does however have
> a tripartite problem of its own that, in my opinion, is just the
> measurement problem blown up. In any case what you say
> afterwords does not follow (from EQM or QM). There are
> non-interactive measurements that people have been looking
> into for a while now (Dicke, Elitzur-Vaidman, etc...). I am sure you
> guys touched on these sometime ago...
> But all of this is irrelevant for my purpose at hand which is for you
> to commit to the proposition that "No-YD: no Bruno"!

We agree it is not relevant for our purpose! Just two words: As a
logician I don't consider Everett proposed a new interpretation of
quantum mechanics, but a new formulation of quantum mechanics. It is
really SWE + comp. (as opposed to the Copenhagen formulation which is
SWE + "an unintelligible dualist theory of mind". Then what I say can
be sum up like this: Everett theory is redundant: SWE follows from
comp. But this is another thread, and we can come back on Everett
"No YD, no Bruno"!?! You make me anxious :)

SWE : Schroedinger Wave Equation
YD: Saying Yes to a doctor who propose you an artificial digital
"generalized brain". First axiom of comp.
(Some people complains out-of-line for the acronyms, so I repeat them
once by mail).

> It seems to me that you are weaseling out of it but I don't quite
> care if you take refuge in another Everett World.
> That
> would be a cop out and I am sure you know it. I want you and I
> digitised IN THIS WORLD! I don't care for copies!

Well: not of copies IN THIS WORLD, I guess. Giving that that is really
the by-product of saying YES to the DOCTOR (YD).

> [GK]
> I don't much care what you can deduce from COMP, Bruno. I care that
> COMP=YD+CT+AR and that shooting down YD would
> shoot down COMP. You could very well deduce from COMP my
> non-existence if YD is false.

Only if YD is *proved* false!!! (I could deduce your inexistence from
the SWE if any TOE (theory of everything) which supposed SWE true, if
SWE is false!). You are saying something very general here!

> BM: Ouh la la. You are close to the 1004 fallacy (asking for more
> precise definition than the reasoning itself). At the start you can
> use the term "axioms", "postulates", "theses", "premises",
> "assumptions", "hypotheses", etc.. in a similar way.
> [GK]
> I think you get my point. I am not asking for precision at all. I am
> pointing out that thesis and doctrines are not hypotheses
> tout court. These three "assumptions" do not have the same epistemic
> status and it is misleading to call them the same.
> If you don't like it, than acknowledge my pragmatics: if your
> point-of-view is falsifiable it should be so without compromising
> either CT and AR which stand very well on their own as you underscore
> below:

Mmhhh... This is your opinion, and perhaps mine. But not of most people
to which my proof is addressed (computer scientist).

> [GK]
> Agreed, than . In any case one unassailable counterexample would
> shoot down CT, deep and " Kleene" as it is (:-)


> [BM]
> Well, I have decided to put it explicitly, because, in front of my
> reasoning, some people cop out simply by saying "Ah, but you are a
> platonist!". So I prefer to say it at once. I agree with you it is a
> sort of "cop out". Now, although 99,99999999 % of the mathematician
> are platonist during the week, most like to pretends they are not (the
> week-end!).
> [GK]
> Ditto.

Hope you are not serious!

> >
> (skiip)
> >
> > (1) YD is obviously independent from CT and AR
> 'course.
> [GK]
> Good!

Well, you will perhaps accuse me of weaseling out again, but thinking
twice, I believe I have answer too quickly in the sense that for saying
yes for an artificial *digital* brain to a Doctor you need to know a
bit what "digital" means, and for this you need CT (Church Thesis), and
for this, I think, you need AR (Arithmetical Realism). But as you say,
CT and AR are mainly bodyguards of YD.

> > (2) GK: CT and AR stand no chance of being falsified empirically
> (or we
>> both like them that way, which is the same).
> [BM]
> I give the opportunity to make comp false in more than one way. If
> you read the Maudlin paper, you will see that he consider the YD
> doctor (or equivalent) as tautologically true (unlike the
> functionnalist hypothesis). This is due to the fact that, unlike many
> older computationalist or mechanist, I put no bound on the
> low-levelness of the substitution level.
> I can say yes to the doctor provided that he simulates my brain at
> the chromodynamical level, including all partiocles having interacted
> with any other particles in the past (in which case my brain is the
> "physical universe" itself. My brain could be a quantum computer,
> without violating comp. The no-cloning theorem does not interfere.
> [GK]
> That is actually where it gets interesting. I will have to sharpen up
> a bit of your YD but in ways that would not invalidate
> your general use of it. More about that later.


> > (3) No one that we know has been able to extract conclusions such as
>> yours from CT & AR without YD (right)
> This is a subtle question. The *necessity* of the reversal is hardly
> understandable without the YD assumption. But once you grasp the
> necessity of the reversal, then the very derivation of natural science
> from computer science does not use it at all. Indeed the cognitive
> science's "grand-mother" is completely substituted by the Lobian
> Machine at this stage. So, with OCCAM razor, once enough of physics is
> derived, you can eliminate the grand-mother and the whole YD
> assumption. Some mathematician asked me to put the UDA argument under
> the form: motivation", and to state that my real "scientific"
> hypothesis are CT and AR. I find that dishonest and misleading,
> because, without understanding the necessity of the reversal, the
> interview of the Lobian machine would resemble to nothing but a little
> piece of pure mathematics, especially given that I have until now
> extracted to few real physics to really call OCCAM. All my papers
> introduce the grandmother (and YD), and then translate the argument in
> the Lobian language.
> But then if the logics of the observables that I have derived from
> comp (at the necessary place) appears to be von Neumann Quantum
> logics, I know people will eliminate the grandmother and the YD, for
> bad reasons (They want pure math, they hate cognitive science, etc.).
> My fear is that people take the epistemological elimination of the
> grand-mother (and the YD assumtion) as an ontological elimination of
> the first person, and nothing could be more wrong than that.
> See the footnote 3. in the SANE paper, and the text
> [GK]
> Bruno, you are weaseling out again, here! Let me ask you this in
> clear terms again:
> Can you, Yes or No, derive your whole "grand manege" from CT and AR
> alone?
> Because if it is a "yes" here I will give you the Oscar (and the
> Nobel) and let you go. I can than concentrate on
> being a good machine for the rest of my existence since I don't want
> to loose my platonic allegiances or my
> heuristic acquiescence to CT.

If by "grand manege" you mean the physical laws: the answer is YES !
(Thanks for the Oscar and Nobel :).
If by "grand manege" you mean deriving the physical laws and
understanding why it is necessarily so, the answer is probably NO. (Nor
could Everett derive the Wave Collapse appearance without something
equivalent to the YD).


> [GK]
> Thanks for the vote of confidence (;-) If I may add a personal note:
> Bruno, I am sure more knowledgeable people than
> myself have pointed out that it is hard to get accross to you because
> you seem so wrapped up in your "demonstration"
> that you express yourself in the language you develop to devise it !

With the YD, perhaps. But then that is why I take 20 years to translate
the argument in pure arithmetics and I have use that translation to
show that comp is 100% testable.

> That is one of the reasons I would rather take you up
> on your premise rather than having to read and judge the rest of your
> paper which I am not even confident I could. I think this is a more
> constructive use of my time and your patience.

But this is just fair! For refuting a proof in applied logic it is
sufficient to show the inconsistency of the premises. If you succeed
not only you really don't need to follow the UDA steps (UDA= Universal
Dovetalier Argument), but nobody will ever need to do that!
Actually the two or three first steps of UDA are just there to make the
premises clearer.
Please note that in the UDA I generally add supplementary hypotheses
which I eliminate later with the Universal Dovetailer.

> What I would like to do next is the following:
> 1) State the YD hypothesis in a way that is both consistent with your
> statement and useful for my purposes. I will
> do that in a separate thread shortly. I need you to agree on that
> version, of course.

Careful: your statement should not just be consistent with YD, but
equivalent to it or at least imply by it to derive something ...

> 2) Once you agree I will tell you a little parable (allegory is more
> platonic, I guess) that illustrates the strict use of that
> statement and the contradition that obtains from it.
> 3) After that I will tell you what that contradiction may be useful
> in settling a certain dispute on the question of
> whether QM has anything to say about consciousness or not.
> OK? What do you say?

I am very interested, Godfrey. Please go and shoot comp. You would be
the first.
But remember that in YD there is a use of folk-psychology or
grand-mother psychology (a fundamental concept of theoretical cognitive
science/philosophy of mind), and then I translate the argument in
arithmetic, and the grandmother will be substituted by the
introspective universal machine (which I call also the "Lobian Machine"
in honor of Lob).

Received on Fri Aug 19 2005 - 05:50:18 PDT

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