Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-10-07 Thread Russell Standish
I'm not so sure that I do perceive positive integers directly. But regardless of that, I remain convinced that all properties of them that I can perceive can be written as a piece of ASCII text. The description doesn't need to be axiomatic, mind you. As I have mentioned, the Schmidhuber ensemble

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-10-07 Thread Russell Standish
Hal Finney wrote: > > I have gone back to Tegmark's paper, which is discussed informally > at http://www.hep.upenn.edu/~max/toe.html and linked from > http://arXiv.org/abs/gr-qc/9704009. > > I see that Russell is right, and that Tegmark does identify mathematical > structures with formal systems

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-10-01 Thread Bruno Marchal
At 19:08 -0400 29/09/2002, Wei Dai wrote: >On Thu, Sep 26, 2002 at 12:46:29PM +0200, Bruno Marchal wrote: >> I would say the difference between animals and humans is that humans >> make drawings on the walls ..., and generally doesn't take their body >> as a limitation of their memory. > >It's

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-09-29 Thread Wei Dai
On Thu, Sep 26, 2002 at 12:46:29PM +0200, Bruno Marchal wrote: > I would say the difference between animals and humans is that humans > make drawings on the walls ..., and generally doesn't take their body > as a limitation of their memory. It's possible that we will never be able to access more

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-09-26 Thread Bruno Marchal
At 12:51 -0400 25/09/2002, Wei Dai wrote: >If we can take the set of all deductive consequences of some axioms and >call it a theory, then why can't we also take the set of their semantic >consequences and call it a theory? In what sense is the latter more >"technical" than the former? It's true

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-09-25 Thread Wei Dai
On Tue, Sep 24, 2002 at 12:18:36PM +0200, Bruno Marchal wrote: > You are right. But this is a reason for not considering classical *second* > order logic as logic. Higher order logic remains "logic" when some > constructive assumption are made, like working in intuitionist logic. > A second order

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-09-24 Thread Bruno Marchal
At 11:34 -0700 23/09/2002, Hal Finney wrote: >I have gone back to Tegmark's paper, which is discussed informally >at http://www.hep.upenn.edu/~max/toe.html and linked from >http://arXiv.org/abs/gr-qc/9704009. > >I see that Russell is right, and that Tegmark does identify mathematical >structures w

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-09-24 Thread Bruno Marchal
At 2:19 -0400 22/09/2002, Wei Dai wrote: >This needs to be qualified a bit. Mathematical objects are more than the >formal (i.e., deductive) consequences of their axioms. However, an axiom >system can capture a mathematical structure, if it's second-order, and you >consider the semantic consequen

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-09-24 Thread Bruno Marchal
At 22:26 -0700 21/09/2002, Brent Meeker wrote: >I don't see how this follows. If you have a set of axioms, and >rules of inference, then (per Godel) there are undecidable >propositions. One of these may be added as an axiom and the >system will still be consistent. This will allow you to prove

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-09-24 Thread Bruno Marchal
At 21:36 -0400 21/09/2002, [EMAIL PROTECTED] wrote: >For those of you who are familiar with Max Tegmark's TOE, could someone tell >me whether Georg Cantor's " Absolute Infinity, Absolute Maximum or Absolute >Infinite Collections" represent "mathematical structures" and, therefore have >"physical e

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-09-23 Thread Tim May
On Monday, September 23, 2002, at 11:34 AM, Hal Finney wrote: > I have gone back to Tegmark's paper, which is discussed informally > at http://www.hep.upenn.edu/~max/toe.html and linked from > http://arXiv.org/abs/gr-qc/9704009. > > I see that Russell is right, and that Tegmark does identify >

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-09-23 Thread Hal Finney
I have gone back to Tegmark's paper, which is discussed informally at http://www.hep.upenn.edu/~max/toe.html and linked from http://arXiv.org/abs/gr-qc/9704009. I see that Russell is right, and that Tegmark does identify mathematical structures with formal systems. His chart at the first link ab

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-09-23 Thread Hal Finney
Russell Standish writes: > [Hal Finney writes;] > > So I disagree with Russell on this point; I'd say that Tegmark's > > mathematical structures are more than axiom systems and therefore > > Tegmark's TOE is different from Schmidhuber's. > > If you are so sure of this, then please provide a descri

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-09-22 Thread Russell Standish
Osher Doctorow wrote: > > From: Osher Doctorow [EMAIL PROTECTED], Sat. Sept. 21, 2002 11:38PM > > Hal, > > Well said. I really have to have more patience for questioners, but > mathematics and logic are such wonderful fields in my opinion that we need > to treasure them rather than throw them

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-09-22 Thread Wei Dai
On Sat, Sep 21, 2002 at 11:50:20PM -0700, Brent Meeker wrote: > I was not aware that 2nd-order logic precluded independent > propositions. Is this true whatever the axioms and rules of > inference? It depends on the axioms, and the semantic rules (not rules of inference which is a deductive conc

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-09-21 Thread Brent Meeker
On 21-Sep-02, Wei Dai wrote: > On Sat, Sep 21, 2002 at 10:26:45PM -0700, Brent Meeker wrote: >> I don't see how this follows. If you have a set of axioms, >> and rules of inference, then (per Godel) there are >> undecidable propositions. One of these may be added as an >> axiom and the system will

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-09-21 Thread Osher Doctorow
lt;[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]> Sent: Saturday, September 21, 2002 7:18 PM Subject: Re: Tegmark's TOE & Cantor's Absolute Infinity > Dave Raub asks: > > For those of you who are familiar with Max Tegmark's TOE, could someone

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-09-21 Thread Wei Dai
On Sat, Sep 21, 2002 at 10:26:45PM -0700, Brent Meeker wrote: > I don't see how this follows. If you have a set of axioms, and > rules of inference, then (per Godel) there are undecidable > propositions. One of these may be added as an axiom and the > system will still be consistent. This will

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-09-21 Thread Osher Doctorow
From: Osher Doctorow [EMAIL PROTECTED], Sat. Sept. 21, 2002 10:39PM I've glanced over one of Tegmark's papers and it didn't impress me much, but maybe you've seen something that I didn't. As for your question (have you ever been accused of being over-specific?), the best thing for a person not f

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-09-21 Thread Brent Meeker
On 21-Sep-02, Hal Finney wrote: ... > However we know that, by Godel's theorem, any axiomatization > of a mathematical structure of at least moderate complexity > is in some sense incomplete. There are true theorems of that > mathematical structure which cannot be proven by those > axioms. This is

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-09-21 Thread Wei Dai
On Sat, Sep 21, 2002 at 09:20:26PM -0400, [EMAIL PROTECTED] wrote: > For those of you who are familiar with Max Tegmark's TOE, could someone tell > me whether Georg Cantor's " Absolute Infinity, Absolute Maximum or Absolute > Infinite Collections" represent "mathematical structures" and, therefo

Re: Tegmark's TOE & Cantor's Absolute Infinity

2002-09-21 Thread Hal Finney
Dave Raub asks: > For those of you who are familiar with Max Tegmark's TOE, could someone tell > me whether Georg Cantor's " Absolute Infinity, Absolute Maximum or Absolute > Infinite Collections" represent "mathematical structures" and, therefore have > "physical existence". I don't know the