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Re: All hail Neo!

From: Frank Hamersley <terabitemightbe_at_bigpond.com>
Date: Sun, 23 Apr 2006 08:19:35 GMT
Message-ID: <rMG2g.13542$vy1.7467@news-server.bigpond.net.au>


Bob Badour wrote:
> Frank Hamersley wrote:
>

>> Bob Badour wrote:

[..]

>>> In that line of thought, here's an interesting question that Date et 
>>> al have posed before to the n-VL folks:
>>>
>>> If "exists but empty" is true and "doesn't exist" is false, what is 
>>> null?
>>
>> Neither and both!

>
> I find that sort of handwaving to be a complete non-answer.

I suspect you are wearing the darkly tinted glasses of preconception. Whilst I was trying to show a little wit, the current 3VL state of affairs still seems to me to fit that description.

> A much more
> intellectually honest reply would be: "I don't know."

Not from this black duck (on this occasion)!

> or "Null has no similar analog in set theory."

I wasn't comparing/contrasting the RM with set theory. Perhaps for you it is implicit?

> True and 1 both have the exact same
> analog in set theory. False and 0 both have the exact same analog in set
> theory.

Perhaps but insistence on a parallel form for the RM does not seem to lead anywhere practical*...FWICT.

> This has a certain elegance and symmetry.

I agree that and readily subscribe to that in my own endeavours.

> In canonical form:
>
> {} = 0 = false
> {{}} = 1 = true
>
> What is the similar analog for null?

My prior knowledge of your/the notation is non existent but I can prolly deduce its intent. So having a stab at it how about ...

{}{} = null

As an aside (and with no malice aforethought) I am curious why the 0 and 1 figure at all? Forced to conform I would probably go with ...

{}{} = -1 = null

Cheers, Frank. Received on Sun Apr 23 2006 - 03:19:35 CDT

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