von neumann machine (Re: is squeak really object oriented ?)
ziakjan at host.sk
Fri May 23 01:51:54 UTC 2003
On Thu, 22 May 2003 21:45:39 -0300, Jecel Assumpcao Jr wrote
> On Thursday 22 May 2003 19:48, jan ziak wrote:
> > i have read the webpage at the supplied location. i draw the
> > following from it:
> > - the automaton is constructed in such a way that IT SUPPORTS the
> > reproduction process. thus, as i said, the organism (in my case it
> > was a glass) must be situated in an environment which provides for
> > its reproduction and thus no object can replicate itself as such.
> Any object takes up resources to exist. Space and mass in the real
> world, for example. Once you reproduce it, the result must take
> twice as many resources. Since the first object didn't exist without
> the environment/resources, I don't understand why it bothers you
> that the new object needs them as well.
> > - an empty cell in von neumann's machine has also its logic, its
> > behavior.
> Just as empty space "has" the laws of physics in the real world.
> > so the question now is: are the empty cells copying the
> > machine or is the machine copying itself? i thin that the answer to
> > this question is that the machine exploits its environment in such a
> > way so that it seems to us that it replicates itself.
> The machine *is* copying itself by any reasonable definition, even
> though it might have to extract resources from its environment to do
> A cell is a self-replicating machine. But not if it is floating in
> space. It can't even function in that situation, so I don't see the
> point of excluding the environment. A strand of DNA isn't a
> self-replicating machine (not even when wrapped in some proteins: a
> virus), so objects must have a certain level of complexity before
> they can copy themselves.
> -- Jecel
we will probably not agree with each other, but never minds. my point of view
is that there is no such thing like "certain level of complexity before they
can copy themselves". because there is no measure for such complexity (except
your definition of self-replication). ....
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