>From: Marchal <marchal.domain.name.hidden>
>Jacques Mallah wrote:
> > I'm a quantum platonist :)
>
>Laugh if you want but one day we will be obliged to
>put clearly our ontological carts on the table [...]
>Well, let me recall you mine: numbers. (natural numbers,
>positive integers).
>[...]
>And I am a classical platonist about the truth on numbers and
>their relations, definable or relatively definable ...
>
>My scientific (third person) ontology = numbers and their relations.
>
>But then I accept intensional interpretations, which adds
>in my set of "ontological truth" the whole of computer science,
>provability logics, ... and ... you and me.
>First person ontology includes the physical laws and you, and me.
I'm not sure what you mean by much of the above. e.g. 3rd person,
numbers' relations, "accept", intensional interpretations, 1st person.
I am a platonist, like I said. The specifics of my position will be
clarified below.
> >I take it, from your above statement, that you do not object to my use of
>the term "implemented". It seems that, in fact, your claim that while I
>have a problem because I need a precise definition of "implementation", you
>supposedly don't, was totally groundless.
>
>Implementation must be some sort of relative computations.
I don't know what you mean by the above, or why you said it. Also, it
does not seem to be a response to my above point.
> > It's hard to define "existence", isn't it?
>
>No. Positive integers exists. Nothing else.
I must point out that you in no way addressed the question of defining
"existence". I am sure you do not mean to say that it is defined as
positive integers! To be pedantic, it is obvious that "the square of 2" is
defined to be "2 x 2" and is not just defined to be "4", even though we
agree (after laborious calculation!) that the number 4 has the property in
question.
>I have no problem if you want more, but in general I don't need it.
>The "right" frontier is somehow arbitrary.
Arbritrary ain't good.
> >Certainly, I would say that whatever structure is responsible for my own
>thoughts must exist in this sense. I only distinguish a "strong sense"
>from the weaker sense used in mathematics, which basically just means
>self-consistent.
>
>Consistency is an attribute of theories or machines or talking ducks,
>not of mathematical object like numbers.
We seem to disagree on what a mathematical object is. For me, anything
that can be described mathematically counts as a mathematical structure. Of
course, an inconsistent description does not describe any math structure.
It is not always obvious whether a given description is consistent or not,
and one way discussion of such a question is often framed is in terms of
whether the hypothetical structure that would be described 'exists'. (e.g.
"Does a power series expansion for f(x) exist?")
>Your use of "basically" hide a confusion between an object and a machine's
>conception of that object.
I don't think so. (Whatever you mean.)
However, there are perhaps three kinds of 'existence' to distinguish.
If a mathematical structure could (in principle) be described, then it
exists in the weakest sense.
A classical Platonist would say that the structure belongs in Plato's
heaven of math; it's a feature of the world which is logically necessary.
This is an intermediate form of existance. (Such an object need not have
any finite description, BTW.)
Let's define a quantum Platonist as one who goes a step further and says
Plato's realm of math is no heaven, but includes our Earth. This implies
the AUH. Unlike the classical position, this requires a unique and
inevitable *measure distribution* on the set of mathematical structures.
My position is that either the classical or the quantum Platonist
position is true, with the latter being more likely (as it explains why
we're here, but in its disfavor it demands a measure distribution).
>You cannot just say physical = mathematical.
>I agree of course, but it is not obvious. It is part of our
>work to make that clear. In particular, in
>that case, we must be able to prove F = ma, or SE.
>
> > We use "physical" to refer to the structure that we guess exists in the
>strong sense. If you believe in the AUH, then the distinction disappears.
>Most people don't.
>
>The distinction disappears ontologically only, but the appearance
>of the distinction does not disappear and must be explained.
We would certainly like to be able to do that. Unfortunately, as I have
argued in other posts, the AUH is not falsifiable, so even if we prove that
F=ma is very unlikely for us to see with the AUH, we are still stuck with
the AUH. But it would be very unsatisfactory, of course. We need to derive
F=ma not to prove the AUH, but to make ourselves happy with it.
> > Leave Everett alone, he is dead and can't defend himself against your
>abuse of his name.
>
>How dare you saying that! And beside have you read Everett?
>I quote it:
>
><<We shall be able to introduce into the theory systems which represent
>observers. Such systems can be conceived as automatically functioning
>machines (servomechanisms) possessing recording devices (memory) and which
>are capable of responding to their environment. The behavior of these
>observers shall always be treated within the framework of wave mechanics.
>Furthemore, we shall deduce the probabilistic assertions of Process 1 [the
>collapse] as *subjective* appearances to such observers, thus placing the
>theory in correspondence with experience.
>We are then led to a novel situation in which the formal theory is
>objectively continuous and causal while subjectively discontinuous and
>probabilistic.>>
>(The theory of the universal wave function, Everett in DeWitt & Graham
>page 9).
For me the key word is "appearances". I am sure Everett did NOT believe
in any discontinuous or probabilistic elements in his interpetation.
Rather, he believed that, for a _typical_ observer-moment, that thought
would include _seemingly random_ information which gave the _illusion_ or
randomness, just like a typical member of the ordered set 000 001 010 011
100 101 110 111 "looks like" a random #.
My interpretation of Everett is proved by his statement that "The
behavior of these observers shall always be treated within the framework of
wave mechanics." This indicates that he did NOT intend to introduce any
"mind-like hidden variables" - and thus, no "1st person" merde about
consciousness "flowing" from one observer-moment to another.
>In my thought experience (UDA and the like) I use *exactly* the
>Everett notion of subjective/objective. I call them first person and
>third person as in classical philosophy of mind.
You just don't understand Everett, it appears. As far as I can tell,
his beliefs were normal (as opposed to crackpot/1st person/mind-like hidden
variable/QTI). Of course, his model of the observer is seriously flawed (it
is not a computationalist model and does not address the reasons for
considering a given set of states to be a 'memory'), but I am sure he would
be the first to admit that it was a good first iteration in what he knew,
right from the beginning, would be a long process toward a truly precise
interpretation of QM.
> >I'm sure that ... he would find my approach to
> >be the logical next step for the MWI.
>
>Now I have the definitive evidence that you or your ancestor are
>french, Monsieur Jacques Mallah, le roi Lion.
Bien sur.
> > > Sure. Yes. UD implements all computations, and even all
>implementations of all computations.
>
> > Great. So you need a precise definition of "implementation" in order
>to find the measure distribution. So much for your claim not to need it.
>
>It is the other way round. I know it is hard to swallow or even just
>to realise I'm serious (and not just poetical) but the physical
>emerges from the wole set of possible consistent continuations, so that
>the "physical implementation" appears only in the logical end.
>An another way to put it is that the physical world is defined by all
>implementations with the weaker sense of any relative computation.
>No first person can ever know how it is implemented.
>With comp the solidity of the physical worlds is a result of the complete
>invariance of first person experience for change among implementations.
I stand by my above statement.
> >Anything real can be stated in objective terms.
>
>I totally agree with you. In particular subjective experience are real,
>and objective proposition can be stated on them (through informal or
>formal definition).
Then there is an objective measure distribution, therefore no QTI or
other '1st person' nonsense.
> >If you say, prior to the duplication "I will either end up
> >in Washington xor in Moscow", that's an objectively false statement.
>
>Correct. I hope you will agree that if you say , prior to the
>duplication, "I will feel myself ending up
>in Washington xor in Moscow", that's an objectively true statement.
>(objectively with comp).
No. (Or at least, incomplete.) It all really depends on the definition
of "me". At this point I can think of three reasonable ways to define it,
but none of them would lead to that statement. The simplest definition is
to define 'me' as a thought; then I exist only for a moment and never leave
my home city.
The closest to what you want would be to define 'me' as a particular
implementation of a computation. I believe that in this case, some of 'us'
would die, some of us would end up in Moscow, while the rest of 'us' would
end up in Washington.
But because the total measure increases in the copying process, bear in
mind that a # of implementations must also be created.
I say that the original implementations would die or split up, but be
joined by their newly created brothers in the new cities. (Mathematically,
recall that I am referring to sets of mappings which satisfy the transition
rules in question. A mapping could refer both to my original body and to
the particles used to create a new body; such a mapping could survive the
transition. I should study this more carefully, e.g. to find out if the
fraction that do this is large or negligable.)
Finally, I could define 'me' as the set of all such implementations.
Then I should say "I will feel myself ending up in Washington and not in
Moscow, _as well as_ in Moscow and not in Washington." (In different
observer-moments, of course.)
> >> > The difference between the first person and the third person is
> >> > basically the same as the difference between having an headache and
>having a friend having an headhache.
> >
> > The above statement makes no sense, unless it is the same as the
> >difference between having a headache, and having had a headache.
>
>Perhaps. Sure if you are willing to believe there is eventually only
>one person. I am open to that idea but quite not convince yet.
It's all a matter of definition, but I have always thought the above to
be a problem for the '1st person' view. What does differentiate different
people?
- - - - - - -
Jacques Mallah (jackmallah.domain.name.hidden)
Physicist / Many Worlder / Devil's Advocate
"I know what no one else knows" - 'Runaway Train', Soul Asylum
My URL:
http://hammer.prohosting.com/~mathmind/
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Received on Sun Apr 08 2001 - 13:21:06 PDT