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Assume v. Presume

Mike0001 said:
There are loads of bogus and incorrect arguments based on such slapdash reasoning. If you discard rigour, as with word meanings, you can never be sure what you end up with. :duel:
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Something that doesn't work properly but completed in a reasonable time.
 
Trev said:
I was 'remembering' from my early learning days many years ago.
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You were taught electrical/electronic engineering in kindergarten? I had to wait until I got a Philips Electronic experiment kit (the one with clips and springs to hold the components).
 
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EEPhil said:
would be wrong in Turing's case.
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So what are you citing as evidence for this - popularist accounts of Engima etc? You're sure he wasn't reliant on the rest of the team and management to keep focus and produce practical results?

My team characteristic is "Plant". Takes one to know one.
 
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Mike0001 said:
There are loads of bogus and incorrect arguments based on such slapdash reasoning. If you discard rigour, as with word meanings, you can never be sure what you end up with. :duel:
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Do any of these "bogus and incorrect arguments" have a practical bearing in real (rather than the imaginary world of mathematics) life? 22/7 is close enough to pi for anything except science (0.04% error - even with a circle 10 feet in diameter, the difference between its true circumference and 44r/7 is only 1mm). 355/113 is the same as pi to within 3 parts in 10,000,000 - definitely close enough for engineering!
 
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So what is the objection to using train? It is possibly less usual than rail or railway (or railroad in N.A.) and in many cases may be deemed an unnecessary adjective since the context tells you the meaning of line, station, etc. But is it wrong?
 
EEPhil said:
You were taught electrical/electronic engineering in kindergarten?
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No.:eek: Infants' school was called Infants' school when I went to school. 'Early learning years' is a relative statement without a fixed time scale. Actually, to put an absolute timescale on this, it was when I joined the RAF in radar electronics in 1961. Is that early enough for you? It was for me.:D
 
MikeSh said:
So what is the objection to using train? It is possibly less usual than rail or railway (or railroad in N.A.) and in many cases may be deemed an unnecessary adjective since the context tells you the meaning of line, station, etc. But is it wrong?
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Well, I was brought up in an era when they were called railway stations, railway lines, etc, and trains pulled by locomotives ran on the railway lines. The current fashion for (even newsreaders) to talk about the "train station" sounds to me like the way one might talk to a three year old: "we're going to the train station to look at the choo-choos". Do you think Network Rail should be renamed Network Train? Maybe that's the problem: the three year olds have now grown up in an era when parental and teacher correction has been abandoned for fear of repressing the creative spirit, and they are now in positions of public communication thinking it's a train station.

It may not be wrong as such, language evolves and not always in a direction the intelligentsia might like, but isn't that what this topic is all about?
 
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Black Hole said:
So what are you citing as evidence for this - popularist accounts of Engima etc? You're sure he wasn't reliant on the rest of the team and management to keep focus and produce practical results?
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Did you not realise that he invented the idea of a computer well before the war even started? In a pure mathematical investigation into decidability, one of Hilbert's unsolved problems, in 1936? Even the idea of a stored programming was there, ready to be refined.
 
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Black Hole said:
22/7 is close enough to pi for anything except science (0.04% error - even with a circle 10 feet in diameter, the difference between its true circumference and 44r/7 is only 1mm). 355/113 is the same as pi to within 3 parts in 10,000,000 - definitely close enough for engineering!
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Black Hole continues digging his hole!

SIGI only uses 16 digit precision. CODATA uses 32. There is more to life than engineering! But how do you think π is calculated? Not mathematically, surely?
 
Mike0001 said:
Did you not realise that he invented the idea of a computer well before the war even started? In a pure mathematical investigation into decidability, one of Hilbert's unsolved problems?
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Yes, but that was just the idea of a computer, as an entirely imaginary device for mathematical investigation (and a Turing Machine is a pretty poor computer, although it might be fun to make one).
 
EEPhil said:
:confused: What the .... are you talking about?
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https://en.wikipedia.org/wiki/Team_Role_Inventories#Belbin_Team_Roles

EEPhil said:
I'm sure Charles Babbage (1791 – 1871) and Ada Lovelace (1815 – 1852) would dispute that, if they could. Do you mean digital computer?
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It's difficult to describe the machines of that era in the same terms as the modern concept of a computer - ie universal, capable of computing anything that can be computed (given enough time and program/data storage). The Turing Machine is a universal computer, but very inefficient in operation, difficult to implement, and a puzzle in itself to program. Nonetheless it was conceived when there were no universal computers, and serves the purpose of a mathematical abstraction.
 
EEPhil said:
I'm sure Charles Babbage (1791 – 1871) and Ada Lovelace (1815 – 1852) would dispute that, if they could. Do you mean digital computer?
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The emphasis there was on arithmetical calculation, surely?
 
Black Hole said:
Yes, but that was just the idea of a computer, as an entirely imaginary device for mathematical investigation (and a Turing Machine is a pretty poor computer, although it might be fun to make one).
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So he built a better one at Bletchley!

It was still a pure mathematician who grasped the idea of a computer that could do any calculation that any computer could, after which it is easy to investigate the capabilities of all computers! He then showed the existence of non computable functions, and that you can never verify in an algorithm whether a computer and programming will behave correctly and find the answers you seek. (Dumbed down paraphrase.)

Yet you still get engineers seeking a program to verify the correctness of any program you give it. There is a practical use of this: stop wasting your time, you are doomed to failure.

As for the Turing machine being inefficient, it is trivial to make it more efficient. It was a means to investigate the limits of computing, not to compute functions in the most efficient way. Machines with registers and stacks are not too far away from the UTM if you read the theory.
 
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