[comp.theory.cell-automata] meta-life

stu@sct60a.sunyct.EDU (Stu Card) (05/09/91)

The responses to I.J. Palmer's question raise the following possibility:
is it possible to define a problem, the solution to which requires an
INFINITE regress up these meta-life simulation levels? I suspect so.

If Life is 'universal', I think that means it is also 'complete' in the sense
of Goedel's Theorem, and therefore inconsistent; otherwise it must be 
'incomplete' (although perhaps 'nearly complete'?!) to keep it consistent.

I am not mathematically heavy enough to know if I am making sense.
Anyone out there with a good understanding of Goedel's Theorem who would
be willing to enlighten me on how it applies to the universality of a 
computing scheme in general, and Life in particular?

stu@sct60a.sunyct.edu
Stu Card

cgl@t13.Lanl.GOV (Chris Langton) (05/09/91)

stu@sct60a.sunyct.edu (Stu Card) writes:

> If Life is 'universal', I think that means it is also 'complete' in the sense
> of Goedel's Theorem, and therefore inconsistent; otherwise it must be 
> 'incomplete' (although perhaps 'nearly complete'?!) to keep it consistent.

No - LIFE belongs to the class of formalisms that is consistent but incomplete. 
LIFE's universality implies that it is subject to the same undecidability
problems as a universal Turing machine, which is the basis for incompleteness. 

   Cheers!

   Chris Langton

   Complex Systems Group
   MS B213, Theoretical Division	Phone: (505) 667-9471
   Los Alamos National Laboratory	Email: cgl@t13.lanl.gov
   Los Alamos, New Mexico, USA		FAX:   (505) 665-3003
   87545