FOM: certainty
F. Xavier Noria
fxn at cambrabcn.es
Wed Jan 6 07:45:42 EST 1999
On Wed, 6 Jan 1999 11:11:02 Arnon Avron wrote:
 On Wed, 23 Dec 1998 0:52:36 +0100 Xavier Noria wrote:

 > We agree what is right about naturals and what not. All our N's have an
 > associative addition, and prime and composite numbers and questions to
 > know the answer, but I think that _truth_ have nothing to do with it.
 >
 > Our N's satisfy that 2 + 2 is equal to 4, but, to my mind, this is our
 > _agreement_ about our abstraction. Saying "2 + 2 = 4 is true" sounds
 > quite different to me.
[snip]
 Unfortunately, I dont feel that I have the right to say what is right
 about *your* N's. How can I know?
I think you cannot know it on your own. We should need to share some
information at least, and I emphasize this is only my opinion.
 since you (and Vladimir Sazonov) have several N's, you have at least one
 which is different from my own poor, lonely N (this only follows, I admit,
 from what is right about *my* logic. You may of course have several other
 logics!). So how can we agree about your N's with which I will never
 possibly have any acquaintance?
Probably, if `several N's' means something like `nonisomorphic models
of a given feasible set of axioms', we'll agree.
Th(N) is the set of firstorder formulas valid in what?
Does your N satisfy GC?
 Xavier
More information about the FOM
mailing list