FOM: certainty

[Andrzej Trybulec]

On Tue, 22 Dec 1998, F. Xavier Noria wrote:

> I cannot understand what "2" or "+" or "4" or, even, "=" would mean, I'm

Who understands it? I mean "2" or "the addition".
Of course anybody understands what "=" means (but the LEGO volk). If you say
that x = y that means that "x" and "y" are two (perhaps different) names
for the same object.

> afraid. I am sorry that I cannot figure out what the "set of the natural
> numbers" could be and what "truth" concerning that concept would signify.

You do not need it. It is advanced mathematics.

> Nevertheless, we would agree if your claim was that "+(ss0, ss0) = ssss0"
> is PA-demonstrable or the like.

Of course not, when you create the union ot two disjoint sets that have 
two elements, both,  then you get four elements and the cardinality of 
the union is four.

Merry Christmas,
Andrzej Trybulec