Le 29-juil.-05, à 05:46, Bill Taylor wrote (FOR-LIST)
> Bruno Marchal <marchal.domain.name.hidden> writes:
>
> ->I would say theology is even more important. <than physics>
>
> !!! ???
I will try to explain. The word "theology" has many connotations. The
word is not so important if you understand the idea.
I have favorite theologians. Plato (who invents the word), but also
Plotinus and "neo-platonist" in general. But also many "oriental"
researchers ...
I could argue that Deutsch's FOR book, or more clearly TIPLER's
"physics of immortality" book are (physicalist) approach to theological
questions.
>
> -> we are still a long way before we succeed in
> ->keeping alive the scientific attitude in that field.
>
> I can only presume you must be speaking of questions of the type,
> "why is there something rather than nothing" and
> "what was there before the big bang" ?
Well not really. I'm just looking to the consequences of our
assumptions.
To say "yes" to a doctor who propose you a digital brain substitution
needs to make a non trivial "act of faith". To say "no", also. Imagine
a pro-life physician who does not believe in mechanism. Heavy
"conscience" problems.
>
> If so, I would have said these were metaphysical questions rather than
> theological ones; and whatever one calls them, they hardly seem to be
> in the same category as what can be treated by science.
I don't believe that there is any field of enquiry where the scientific
attitude should not be applied. Scientific attitude, I think, is not
much more than modesty.
The more fundamental are the questions, the more modest the "scientist"
should be.
>
> -> The subject is still too hot.
>
> And too vague.
Vagueness is not necessarily a problem, unless it is (mis)used by
people who wants manipulate other people. Less vague statements are
born from more vague statements.
Degree of vagueness could also depend on the assumptions.
>
> ->Most theological questions are still buried under the carpet,
>
> Where they belong.
The problem is that if the "scientist" dismiss some fundamental
questions, they will be tackled by those who will use some urgency
feeling related to them to to do "total unrigorous manipulative
pseudo-theology", so that the scientist will say "you see, let us keep
those things under the carpet". Your negative attitude is unfounded and
self-fulfilling, I'm afraid.
>
> ->or dismiss as non scientific.
>
> As I have just done.
No sincere questions are "non scientific". Prejudice against some
possible sense in those questions will not help making them more clear
and, who can know in advance, susceptible to scientific progress on
them.
>
> -> All this is helped by many "materialist or atheist superstitions".
>
> One doesn't need to be either of those things in order to question
> the appropriateness of metaphysical matters to scientific ones.
Some scientists pretend not doing metaphysics, but when you dig a
little bit you realized they believe in Nature or in a primitive
physical world. That *is* a metaphysical opinion.
If you really want to avoid "useless *metaphysics*" then you should be
more open to the possibility of progress in theological matters.
Indeed, in *any* matter.
>
> ->Also, if you assume the computationalist hypothesis, like David
> Deutsch,
>
> I have earlier noted that this would more accurately be called
> the "Matrix" hypothesis.
>
> -> then there is a case that Physics emerges from Mathematics and Logic
>
> As I earlier convincingly (IMHO) showed, this can be rejected on
> categorical grounds alone, apart from any other consideration.
So you confess that you think there is no need to look at my argument
because you find the conclusion already inconsistent. At least you are
frank. Yet I would appreciate a more constructive critics. If you are
so sure you could play the game of finding the error in the
argumentation you refer to.
>
> -> so that it is clearly testable.
>
> It is not. In the same sense that solipsism is not testable.
You don't get it at all. Apology for pointing to my work: I have given
two things. First a deductive argument showing that if we make a
precise hypothesis in the "cognitive theoretical science" it follows
necessarily that physics is derivable from computer science. The
"simplicity" of the argument is provided by the high non-constructivity
of the proof. But then I translate that argument in the language of a
sound universal turing machine (with enough "introspective ability")
from which I derive the logic of the "observable propositions". To put
it bluntly I can sum up the main technical result by the shape of the
arithmetical translation of the argument:
PHYSICS = SOL ° THEAE ° COMP (G),
where SOL, THEAE, and COMP are the main components of the translation
of the "reversal" arguments. Mathematically they are well defined modal
logic transforms, so that we can test the result. Unfortunately,
although the propositional physics is decidable, even "easy question"
like Bell's inequality, symmetry of nature, no-cloning theorem, etc.
are still intractable. Yet I got intermediary result showing that only
an arithmetical conspiracy would make those questions in principle
intractable, and I did actually derive a sort of curious "quantum
logic".
I train myself often to explain more and more the technics on the
everything-list where people have similar approaches. You are welcome.
You could even help perhaps. Actually I have just finish a paper which
I find rather better than the preceding one. I progress toward a paper
which would correspond to an english revised version of my PhD thesis.
I am slow, but the subject is tricky, and is confronted with many
deep-engrained philosophical prejudices. I do have under-estimate the
tabu features of the questions I am interested in.
Note the FOR book *is* an excellent introduction to those questions and
I do share many important views on the nature of science with David
Deutsch (and Rafe Champion).
>
> -> but then as he said himself he must disagree
> -> with all mathematicians and computer scientist on Church's thesis.
>
> Very true, very true.
I know we agree on this. Given that Church Thesis is a key part of the
hypothesis I mention above I am sure you could understand what I try
(at least) to convey. I just say that the computationalist hypothesis
leads to mathematically and experimentally verifiable statements. And
this constructively (after making first the main point in a
non-constructive way).
By the way, with the comp hyp, by "theology" you could "just" mean the
search of all what is true *about* machines, including what is true but
non justifiable by them.
Theoretical computer science permits then to study "toy" machine
theologies, and it is already interesting to discover how infinitely
complex the related mathematical questions are, making you perhaps more
modest, and thus ... "more scientific".
Bruno
http://iridia.ulb.ac.be/~marchal/
Received on Sat Jul 30 2005 - 12:47:03 PDT