Darren New schrieb:

> Having the program in hard wiring doesn't make it impossible to be 
> Turing complete. *That* is what I was arguing.

If a machine can only be programmed by hard wiring, and none of the hard 
wiring options implements a capability for soft programming, then it 
/is/ impossible to be Turing complete. That is what /I/ was arguing.

>> I'm perfectly aware of that. But it is a misconception to think that 
>> the architecture of a computing device must necessarily be akin to 
>> that of a Turing machine.
> 
> Huh? When did I ever say anything close to that?
> 
> All I asserted was that "reprogramming requires rewiring" is orthogonal 
> to "is not Turing complete."  At *some* level of abstraction, every 
> computer requires rewiring in order to reprogram it.

You did, as a matter of fact, assert that Colossus could have been 
hard-wired into a UTM, provided it had enough cables to re-wire.

Aside from that: Yes, any soft-programmable machine - including (but not 
limited to) any such Turing machine - does have a hard-wired programming 
at its core, so /any/ computing device can be reprogrammed by re-wiring. 
However, if a device's hard-programming does not (and cannot) provide 
for any means to program it at a non-hardware level, that /is/ contrary 
to being Turing complete: a UTM, by definition, reads the details of the 
Turing machine to simulate (viz: the program) from its tape, i.e. the 
program is part of the data it works on. To simulate a UTM, you need to 
simulate this aspect as well, therefore being Turing complete /requires/ 
the ability to be re-programmable without re-wiring (at least in /some/ 
wiring configuration).

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