
The Man Who Invented the Computer - robg
http://www.nytimes.com/2010/11/28/books/review/Schulz-t.html?ref=technology
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rmoriz
The ABC was not a computer as in "turing complete". The first "turing
complete" computer was Zuse's Z3.

see <http://en.wikipedia.org/wiki/Computer>

~~~
kleiba
I attended a conference once where the invited speaker, Raul Rojas, showed
that the Z3 was a universal computer, which wasn't previously believed to be
the case. The basic idea of the proof was to show that you could have a single
while-loop on the Z3 containing a big case-statement in the body of the loop
which basically simulates a (finite) Turing machine.

The interesting part of this talk however was this: the Z3 did support neither
loops nor conditional branches per se! Instead, it could just compute a series
of mathematical operations encoded on a punched tape.

To simulate the case statement without the conditional branching, the trick
you do is you execute every branch of the case-statement each time, but you
only allow one of the branches to write the results of its computation back to
the machine's memory.

But how do you get a while-loop? Well, you just glue the ends of the punch
tape together! ;-)

(More details here:
[http://www.zib.de/zuse/Inhalt/Kommentare/Html/0684/universal...](http://www.zib.de/zuse/Inhalt/Kommentare/Html/0684/universal2.html))

~~~
scott_s
But was it used as a general purpose machine? I think there's a difference
between something that was designed and used for general purpose computation
and something that was only demonstrated to be able to do general purpose
computation after decades of hindsight.

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scott_s
For the other side of this, read "ENIAC: The Triumphs & Tragedies of the
World's First Computer" by Scott McCartney. The work Eckert and Mauchly put in
to get the first electronic, general purpose computer in a state that it was
useful to others should be interesting to anyone who reads HN. It's both a
story of hackers and entrepreneurs.

I take issue with this characterization: "Mauchly was not a better scientist
than Atanasoff, but he was a more ambitious entrepreneur."

Mauchly did something Atanasoff did not: he made something _useful_. So
useful, in fact, every digital computer you see in front of you is a direct
descendant of Mauchly's labor, not Atanasoff. Eckert and Mauchly drew
inspiration and ideas from many places, but I think people here should be able
to sympathize with the fact that these two were the leaders behind the project
that made those ideas a useful technology that changed the world. While those
ideas existed before Eckert and Mauchly did their work, they're the ones who
put in the grunt work to fully realize them - and contribute their own
innovations along the way.

I actually find the portrayal of Eckert and Mauchly in the whole piece real
disheartening.

~~~
bsk
>> So useful, in fact, every digital computer you see in front of you is a
direct descendant of Mauchly's labor, not Atanasoff.

This doesn't make any sense. Atanasoff had some pretty genius ideas and
together with Berry built the first electronic digital computer. Mauchly
visited their lab, got a ton of information on ABC and later built another
electronic digital computer - ENIAC, which was generally ABC 2.0.

~~~
scott_s
ABC was not a general purpose computer - it was not Turing Complete. It was
not in continuous development by the time Mauchly saw it - that was the end of
the line for the ABC. Eckert and Mauchly, on the other hand, developed a
general purpose electronic computer with the explicit goal of getting it out
to as wide an audience as possible.

~~~
bsk
Hmmmm, IMHO every statement here is incorrect.

Do you have a mathematical prove that ABC is not Turing Complete? I suspect
that if one is sufficiently smart, he can implement a Turing machine on top of
any 1930s, 1940s computer.

BTW I don't think 'General purpose computer' is used widely as equivalent of a
'Turing complete computer'.

From
[https://secure.wikimedia.org/wikipedia/en/wiki/John_Vincent_...](https://secure.wikimedia.org/wikipedia/en/wiki/John_Vincent_Atanasoff)
: "In June 1941 Mauchly visited Atanasoff in Ames, Iowa for four days, staying
as his houseguest. Atanasoff and Mauchly discussed the prototype ABC, examined
it, and reviewed Atanasoff's design manuscript. Up to this time Mauchly had
not proposed a digital computer. In September 1942 Atanasoff left Iowa State
for a wartime assignment as Chief of the Acoustic Division with the Naval
Ordnance Laboratory (NOL) in Washington, D.C. ... Mauchly visited Atanasoff
multiple times in Washington during 1943 and discussed computing theories, but
did not mention that he was working on a computer project himself until early
1944.

By 1945 the U.S. Navy had decided to build a large scale computer, on the
advice of John von Neumann. Atanasoff was put in charge of the project"

Sounds to me like Mauchly just tried to steal Atananasoff ideas (with some
success).

~~~
calceranog
Please simply compare the features of the ENIAC with the ABC, and tell me
where the similarity lies: ABC operated in binary, while ENIAC was decimal.
ABC used vacuum tubes as flip-flops, making it essentially an electro-
mechanical machine operating at one operation per second. ENIAC used vacuum
tubes as electronic counters, making it operable at electronic speeds, i.e.,
5,000 operations per second. ABC was designed to process one type of problem
(differential equations), while ENIAC was indeed general purpose, and could be
programmed to handle any problem, including the insanely complicated
mathematics of the hydrogen bomb. If you want to fault Mauchly for talking
with other scientists while planning his own computer, then please also
include all the other scientists with whom he shared ideas. Also note that the
two met when Atanasoff attended a lecture Mauchly was giving ... on the use of
electronics in computation. Does this sound like Mauchly got all his ideas
from Atanasoff? Also, BTW, Mauchly kept "visiting" JVA's lab at NOL because HE
WAS HIRED BY THE NOL TO CONSULT ON THE PROJECT because it was making very
little progress under Atanasoff's direction. Look it up.

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Osmose
Depends on your definition of computer, of course. I've always heard that
Babbage invented the computer.

<http://en.wikipedia.org/wiki/Babbage>

~~~
dhs
Yes, it's very much a matter of perspective, which is why I find it so
fascinating. Babbage is clearly a candidate, as is Konrad Zuse [1], who built
the first functional Turing-complete machine, and designed the first Turing-
complete programming language [2] (it didn't have recursion, but neither had
FORTRAN, before the mid-70s). Bottom line (for me): computers are the result
of international and cross-generational cooperation and knowledge exchange;
that's were progress seems to come from.

[1] <http://en.wikipedia.org/wiki/Konrad_Zuse> [2]
<http://en.wikipedia.org/wiki/Plankalk%C3%BCl>

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aptimpropriety
If the link asks you to log in, going through Google News works (top link -
Binary Breakthrough):

[http://news.google.com/news/search?aq=f&pz=1&cf=all&...](http://news.google.com/news/search?aq=f&pz=1&cf=all&ned=us&hl=en&q=the+man+who+invented+the+computer)

~~~
ronnier
In addition, you can use my weekend project:

[http://viewtext.org/article?url=http%3a%2f%2fwww.nytimes.com...](http://viewtext.org/article?url=http%3a%2f%2fwww.nytimes.com%2f2010%2f11%2f28%2fbooks%2freview%2fSchulz-t.html%3fref%3dtechnology)

~~~
PostOnce
Have you gotten a C&D letter yet? :P

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aquarin
There is a high school of electronics in my town with J. Atanasoff name.

