Billy Brown, <bbrown@conemsco.com>, writes:
> hal@rain.org wrote:
> > A. It is a matter of interpretation whether a given system can be
> > described as a computer running a specified program P
>
> This proposition is definitely false.
>
> It is true that information content is largely observer-dependant, in the
> sense that I can choose any scheme I like for mapping physical phenomena to
> data. In this sense you could view any complex object as encoding all sorts
> of different programs, using many different schemes. However, this does not
> imply that any system can be interpreted as 'a computer running a specified
> program P'.
So would you agree that my couch could be interpreted as having the same structure as any given program P? Perhaps even that the couch could be interpreted as encoding the same structure as a snapshot of Einstein's brain? And that the reality and validity of this interpretation is as strong as viewing Einstein's brain as encoding that same structure?
> [...]
> The problem lies in the fact that a computer is not a static body of data.
> One could view your couch as encoding a complete blueprint for my computer,
> but that is not the same thing as actually being one. To qualify as
> actually being a computer, your couch must display a certain range of
> behaviors in response to environmental stimuli. It has to maintain an
> ongoing chain of appropriate, causally connected states while running a
> program. The thermal vibrations in your couch are never going to display
> this behavior, no matter what encoding scheme you use.
Or is the issue here the fact that the sequence of structures are not "causally connected"? We can set up a mapping by which the couch goes through a sequence of states with the same structure as a sequence of states in Einstein's brain. But perhaps we would say that the causal relationship of these states is not the same, because *if* we had tweaked some aspect of Einstein's brain state at a given moment, it would have led to changes in the pattern of succeeding states. But making the corresponding change to the state of the couch would not have led to the same kind of changes in the succeeding couch states.
Hal