17 Sep
2015
17 Sep
'15
4:49 p.m.
From: Paul Koning
Sent: Thursday, September 17, 2015 9:02 AM
In any case, I do not believe the original statement.
First of all, it is
well known that no computer can solve "all problems" (see G?del). For those
it *can* solve, as far as I know, a Turing machine can solve a superset of
what a stored program computer can handle,
All right so far.
and a Turing machine does NOT have self-modifying
code.
<choke><spit><soda on keyboard>
Excuse me????
A Turing machine is the very essence of self-modifying code, by its very
definition! You have the infinite memory tape, divided into cells, a reader,
and a writer. The reader looks at a cell and performs the action required by
the symbol read there. Possible actions include erasing the symbol already
present and writing a new symbol; once that is done, the reader looks at the
new symbol and performs the action required by *that* symbol.
Lather, rinse, repeat. (Interrupt when out of shampoo.)
Rich
Rich Alderson
Vintage Computing Sr. Systems Engineer
Living Computer Museum
2245 1st Avenue S
Seattle, WA 98134
mailto:RichA at LivingComputerMuseum.org
http://www.LivingComputerMuseum.org/