From: Bob Kolker on
Eckard Blumschein wrote:

>
> Any rational number has a numerical address. Just the entity of all
> rational numbers is a fiction.

The set of rational numbers exists in exactly the same sense that the
set of integers exists.

Bob Kolker

From: Lester Zick on
On 30 Nov 2006 23:55:39 -0800, "Tonico" <Tonicopm(a)yahoo.com> wrote:

>
>Lester Zick ha escrito:
>........................................................
>> >> >What sort of evidence? Surely not empirical evidence. Mathematics done
>> >> >abstractly has no empirical content whatsoever.
>> >>
>> >> Except apparently for axioms and definitions.
>> >******************************************************************
>> >What axioms of what part of maths have "empirical" evidence in the
>> >sense Eckard is tryuing to convey?!?
>>
>> I don't know what sense Eckard is trying to convey. My response was in
>> reply to Bob not Eckard.
>
>******************************************************************
>Bob was answering Eckard's ranting, and you got in the middle talking
>something about axioms...and you don't know what Eckard was trying to
>convey?

Why should I care what Eckard was trying to convey since I was
replying to what Bob was trying to convey to which he appears to have
nothing to convey.

>******************************************************************
>
>> > For him, and for other trolls,
>> >Cantor "not having evidence" for his idea (what stupid this sounds!)
>> >means that he (cantor) never foiund an aleph_null under his bed, or
>> >that so far no one can buy aleph_beith apples out there.
>>
>> Well empirical evidence would certainly be one criterion for the truth
>> of what one claims.
>
>****************************************************************
>"Truth"?? Who gets to define what "truth" is, except religious
>fundamentalists and other cuckoos of the kind?

Certainly not modern mathematikers.

> And what do we care of
>that in maths?

Indeed.

> The basic questioning for a mathematical set of axioms
>is, imo, whether it is a consistent such set...and whether it is
>interesting to deal with, of course. If you mean this by "truth" then
>fine.
>****************************************************************

No it is not what I mean.

>Otherwise one is forced to rely on analytical
>> criteria for the the truth of infinities which no modern mathematikers
>> appear willing to assert and demonstrate.
>
>****************************************************************
>Again: what does "the truth of infinities" in the mathematical world
>mean?

Produce them either empirically or prove them analytically instead of
just assuming what you're talking about. In other words show the truth
of what you're talking about or shut up. Shape up or ship out.

> And again: I don't think any mathematician is interested at all
>in assert and demonstrate whatever about "truths" (whatever the meaning
>of that is for you), UNLESS you're referring to consistency of axioms,
>relevance, interest....and all this has been widely done the last 130
>years or so.
>***************************************************************

So you speak for all mathematics do you?

>> >What "empirical evidence" are there in group theory's axioms? Or in
>> >Topology?
>>
>> The axioms and definitions themselves are empirical.
>
>****************************************************************
>Perhaps it is that we don't really understand what each other means by
>"empirical". For example, what empirical evidence (of what, where,
>when...?) does the axiom stating the existence of a unit element in
>group theory have? Or the axiom in Topology that states that the empty
>set is part of the set of open sets?

I agree we don't understand the term "empirical" the same way. Not my
fault since I've discussed the subject at length over the past couple
years here and elsewhere. Basically any tautologically undemonstrated
judgment is empirical. Doesn't matter whether the judgment is sensory,
perceptual, cognitive, or whatever. If you assume an axiom such as "a
straight line is the shortest distance between points" the assumption
is empirical until and unless demonstrated true analytically. The same
applies to definitions.

Most people completely misunderstand the meaning of an empirical
judgment. Most think it means getting out the tape measure, scales,
and so forth. The problem originated with Aristotle and his concept of
syllogistic inference. Aristotle was history's first empiricist in
formal terms. He found he could not establish the truth of any
conclusion syllogistically except by regression to further premises
whose truth he could not establish either except by further regression
ad infinitum. Which meant he could establish no truth syllogistically
at all without some kind of true basic premises which he set out to
find in unreducible perceptual terms. Which left us epistemologically
exactly where we are today in terms of all kinds of mathematical and
scientific methodologies.

In point of fact however empirical judgment is nothing more than input
to a process of tautological regression whose ultimate goal is
reduction to self contradictory alternatives. That's how the mind and
brain work, tautological rather than syllogistic inference because it
can produce reductions to truth in exhaustive mechanical terms.

~v~~
From: MoeBlee on
Bob Kolker wrote:
> MoeBlee wrote:
>
> >
> > What ordering do you claim to exist on the Cartesian plane? How do you
> > prove its existence? What kind of ordering is it (what are its
> > properties from those I mentioned)?
>
> Without resorting to the axiom of choice or well ordering one can use
> the lexicographical ordering (alphabetic ordering of two letter words,
> so to speak) of two tuples. But this ordering has no arithmetic
> significance.

Right, of course we can take the lexicographic ordering on ordered
pairs of reals, since the reals have an ordering (even a linear
ordering). But in this case, what are the ordering properties? In this
case, what kind of ordering - quasi, partial, simple, linear, etc. - is
it? (But my original question was to know what kind of ordering TONY
claims to exist, since in the past he's even claimed to prove the
existence of a well ordering of the reals even without assuming an
axiom such as choice or well ordering.)

MoeBlee

From: Tony Orlow on
Bob Kolker wrote:
> Tony Orlow wrote:
>
>> Are x and y ordered? The Cartesian plane is ordered in two dimensions,
>> not a linear order, but a 2D ordered plane with origin.
>
>
> The plane is not a linearly ordered set of points.
>
> Bob Kolker

That's what I just said.
From: MoeBlee on

Tony Orlow wrote:
> Bob Kolker wrote:
> > Tony Orlow wrote:
> >
> >> Are x and y ordered? The Cartesian plane is ordered in two dimensions,
> >> not a linear order, but a 2D ordered plane with origin.
> >
> >
> > The plane is not a linearly ordered set of points.
> >
> > Bob Kolker
>
> That's what I just said.

So what kind of ordering do you contend it is?

MoeBlee