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Topic: A finite set of all naturals
Replies: 43   Last Post: Aug 25, 2013 4:38 PM

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 quasi Posts: 12,023 Registered: 7/15/05
Re: A finite set of all naturals
Posted: Aug 23, 2013 5:03 AM

Peter Percival wrote:
>Nam Nguyen wrote:
>>
>> I certainly meant "odd(x) can _NOT_ be defined as a
>> positive formula ...".

>
>Prove it.

With Nam's new definition of positive/negative, I think
it's immediately provable (subject to some clarification as
to what a formula is) that odd(x) is a negative formula.

Let even(x) <-> Ey(x=2*y).

Assuming Nam's definition of "formula" supports the claim
that even(x) is a positive formula, then odd(x) must be
a negative formula since odd(x) is equivalent to ~even(x).

So, conceding that, where does he go with it?

quasi

Date Subject Author
8/22/13 namducnguyen
8/22/13 namducnguyen
8/23/13 Peter Percival
8/23/13 quasi
8/23/13 Peter Percival
8/23/13 namducnguyen
8/23/13 Peter Percival
8/24/13 Peter Percival
8/24/13 namducnguyen
8/23/13 Shmuel (Seymour J.) Metz
8/23/13 namducnguyen
8/23/13 Peter Percival
8/23/13 namducnguyen
8/24/13 Peter Percival
8/24/13 namducnguyen
8/24/13 Peter Percival
8/24/13 Shmuel (Seymour J.) Metz
8/25/13 namducnguyen
8/25/13 Peter Percival
8/25/13 fom
8/25/13 Shmuel (Seymour J.) Metz
8/24/13 Shmuel (Seymour J.) Metz
8/24/13 Shmuel (Seymour J.) Metz
8/23/13 tommy1729_
8/23/13 Peter Percival
8/23/13 namducnguyen
8/23/13 Peter Percival
8/23/13 namducnguyen
8/24/13 Peter Percival
8/24/13 namducnguyen
8/24/13 Peter Percival
8/24/13 namducnguyen
8/24/13 Peter Percival
8/24/13 namducnguyen
8/24/13 Peter Percival
8/24/13 fom
8/24/13 Ben Bacarisse
8/24/13 namducnguyen
8/24/13 fom
8/24/13 Peter Percival
8/24/13 fom
8/25/13 Peter Percival
8/23/13 Shmuel (Seymour J.) Metz