Some comments

From: Marchal <marchal.domain.name.hidden>
Date: Tue May 30 07:57:27 2000

Some comments:

George Levy wrote:
>Right Fred. You are on the right track. To all those die hard absolutist
>objectivist computationalists, here is a puzzle. What is the purported
>Universal Turing Machine made of? :-)

Immaterial and atemporal relations between numbers :-)


Higgo James <james.higgo.domain.name.hidden> wrote:
> the ideas Bruno, Jacques and I put forward are
> idealist.

 ...and Jacques Mallah answered:

> My view is that math is fundamental. Ideas should
>be derivable from the math of computations. The
>physical world is real in that it is mathematical.

OK Jacques. But then I call you a (platonist sort of)
idealist. (Just a question of terminology).
And I'm not sure I understand the "the" in "the physical world".


Brent Meeker wrote:

>It depends on what you take as fundamental. From a Cartesian viewpoint,
>thoughts and perceptions are fundamental - all else, including physics, is
>inferred and constructed from the coherence and relations we perceive.
> Hence
>to use physics to explain that coherence and consistency is somewhat
>circular.

Yes. Absolutely. Fundamental point.


Jacques Mallah wrote:

> In the case of observers, implementing a conscious
>computation (OM) can be a property of the substrate,
>and this property I consider automatically present if
>the math is right without needing psychophysical laws.
> I thus reduce consciousness to math.

What substrate? How will you define or recognize a
substrate within the math. I think I agree with you, except
I am not sure you actually propose a precise mean for
the reduction of consciousness to math.
And I don't expect you to be able to do that without
distinguishing 1 and 3 person point of view, *in the math*


> Brent Meeker :

>But it is just my point that assuming we are rational is too much too
>assume.
>I'm not even sure "rational" is well defined. If you look in Robert Nozick's
>book, "The Nature of Rationality" you find ideas about will and purpose -
>which
>is very far from what is usually meant on this list. The rationality you
>would
>have filter the Plenitude is rationality of scientific objectivity, the
>ability
>to agree on observations. Even if "rational" in this sense is well
>defined, it
>is obivous to me that many people are not rational - does that change the
>world? Do they live in a different universe - I thought that was just a
>figure
>of speech. That's why I find interesting the arguments that attempt to
>impose a
>probability measure on the Plenitude and show that the world must (with
>probability one) be predictable/rational.

This is indeed what most of us are trying to do. Now, by capturing
rationnality by "formal provability and consistency" I propose a way
to isolate a measure on the set of computations appearing in the UD.
This is more technical. I will come back with this point in a futur
post.


Russell Standish wrote:

> Time is a psychological
>entity. I have no problem with this. If one accepts Bruno Marchal's
>conclusion, Physics and Psychology are ontologically reversed ...

Glad to hear that.

> ... All
>physical concepts are fundamentally psychological phenomena. I suspect
>that this conclusion actually follows from the Plenitude + Anthropic
>Principle, without the need of some of Bruno's strong AI type
>assumptions, but that remains to be seen.

Perhaps. The advantage of the ``strong AI type assumptions" is that
the mind body problem and the problem of the origin of the belief
in ``natural" law can be extracted from a measure on the UD, which is a
big whole well defined (with Church thesis). You don't have the equivalent
of Church thesis for more than computations.


Brent Meeker wrote:

>The WAP permits wabbits - the miracles some people see. One of the
>interesting ideas deriving from the Plenitude is that by assigning some
>measure to the universes that can exist one may be able to prove that
>wabbits have vanishing probability. I haven't seen a way of assigning
>this measure that seems completely convincing in detail, but the idea
>seems right.


Finding the measure is not enough. We must explain the unicity of that
measure. Glad you say the idea seems right. But in my approach you should
subtitute universes by computationnal histories "seen from within."

Brent Meeker wrote:

>Bertrand Russell showed that time as a continuum could be constructed from
>finite perceived intervals. The ordering relation is given by the overlap of
>the intervals. It seems to me that these discussions are sometimes
>confused as
>to whether the argument is going to take a Cartesian direction from something
>we perceive directly -- "there is a thought" -- to the apparent physical
>world
>or instead to assume some Platonic ideal --- the ensemble of all logically
>possible worlds -- and try to show that it makes us and our world at least
>probable. These are both interesting approaches and need not contradict; but
>it gets muddle when one slides from one to the other.


It is the first (cartesian) one from a local 1-person point of view.
But it is the second one (Platonic ideal) from the Sirius 3-person point
of
view. Not only these are both interesting and not contradictory
approaches,
but these are both inescapable.

Bruno
Received on Tue May 30 2000 - 07:57:27 PDT