From: Kev Jackson <kevin.jackson@...>
Date: 2005-08-12T13:43:51+09:00
Subject: Re: NEWBIE QUESTION: pattern with nil


>> Um. No wonder you're having problems, if you are trying to teach him
>> things that aren't real. I'll be the first to admit that I'm weak,
>> but I don't recall arithmetic or numerical theory being based on set
>> theory (that is, numbers as sets).
>
>
> http://mathworld.wolfram.com/OrdinalNumber.html
>
Yeah I have to agree here, integers are a Set of values based on a 
single number line (according to my recollection), 
reals/floats/engineering units are also a Set of values that exist on 
this line (with them both exist the negative values), and for complex 
numbers we have to expand into 2 dimensions.  The Set theory of numbers 
allows us to perform proof by induction (I think, it was a while ago) - 
ie if something is true for n, then we can prove for n+1.  I'm pretty 
sure that was what 4 courses on (2)formal methods + mathematics + 
algorithm design were trying to teach us - of course we were all 
concentrating on the hot russian blonde in the front row!  And I have to 
admit to having never used this information professionally (hence it's 
incredible rustiness), so I could be miles out.  If so, sorry.

Kev