On 24 Apr 1998 modlin at concentric.net wrote:
> In <6hqseq$q8n at ux.cs.niu.edu>, rickert at cs.niu.edu (Neil Rickert) writes:
>> [modlin] What is your definition of computation?
>> >A computation is a set of causal operation which take place in the
> >world, and which have a certain kind of mathematical description.
>> [modlin] Under your rules, is a Turing machine capable of computation?
>> >No. It is capable of formal computation, but not of computation,
> >where formal computation is a mathematical idealization of
> >computation.
>> Interesting. Your conflation of "computation" with notions of
> physically realized causality is something I've not encountered
> before...
BJ: Leibniz argued for a similar view, but he has largely been ignored.
Can you carry out a computation in a (natural or artificial) system which
does not respect physical causality? How do you account for Wigner's
'unreasonable efficacy' of mathematics with respect to the 'real',
'physical' world? Is it not perhaps 'because' our theories are abstracted
from that world?
Computation is an abstraction, inherently distinct from the engineering
practicalities of a device > which might instantiate it.
BJ: Can you name a computation which exists apart from a set of hardware
or wetware?
