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

 Messages: [ Previous | Next ]
 namducnguyen Posts: 2,777 Registered: 12/13/04
Re: A finite set of all naturals
Posted: Aug 23, 2013 2:42 PM

On 23/08/2013 8:55 AM, Shmuel (Seymour J.) Metz wrote:
> In <ghae19tt5it7c9phdr64quip03q2dmdl29@4ax.com>, on 08/23/2013
> at 04:40 AM, quasi <quasi@null.set> said:
>

>> 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).
>
> Let odd(x) <-> Ey(S(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).

>
> However, even(x) is equivalent to ~odd(x), so even(x) must be a
> negative formula.
>
> You can exclude S, but then you're no longer talking about the natural
> numbers.

You seem to be confused on the issue, which is that _in the natural_
_numbers_ while even(x) can be positively expressed _with only_ '*'
can the same be said of odd(x)?

--
-----------------------------------------------------
There is no remainder in the mathematics of infinity.

NYOGEN SENZAKI

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