Re: Set theory and hyperset theory

Onar Aam (onar@HSR.NO)
Thu, 24 Aug 1995 00:23:42 +0100


In-Reply-To: Your message of "Wed, 23 Aug 1995 10:45:21 GMT ." <199508231012.MAA05384@broremann.hsr.no>

>I agree (isn't this what I said?).

Sure. Sorry if I reiterate what is already pointed out.

>> A={not(A)}
>>
>> this can be translated into a hyperset equation by letting not(A)=B. We then
> get
>> the following hyper-equation:
>
>I don't think this is adequate. An essential property of negation is
>that you can't have both A and not(A), without something being wrong.
> Otherwise it is not negation (It's life Jim, but not as we know it!).

I think you missed my point here. Hyper-sets cannot hold negations, that would
be a true contradiction, but hyper*functions* can. You must then view NOT as a
transformation i.e. a function. Hyperfunctions have the general form A = F(A).
In the special case above F(A) = not A. This is a logically consistent
transformation of A, even though the equation at hand is a contradiction.

>A similar argument may work from B in hyperset theory! B is 'more'
>than infinite! (I know that sounds silly - but true. B contains all
>the infinite ordinals and their contents, in fact of all the ZF
>sets).

Yes, I had a feeling about this. Thanks for pointing it out.

Onar.