Re: OT: Solipsism

On Mon, 23 Jan 2006 10:05:53 +0100, Dirk Thierbach
<dthierbach@xxxxxxxxxxxxxxxxxxx> wrote:

>John Brock <jbrock@xxxxxxxxx> wrote:
>
>> The logic part may be considered to be tautological (how else would
>> one even define a tautology other than by appealing to the rules
>> of logic), but the axioms are not tautologies, they are bald
>> assertions that we accept because they appear to us to be self-evidently
>> true.

<snippo>

>Take geometry: The axiom that for each line, and a point not on this
>line, there is exactly one line through that point that is not identical
>to the first line describes euclidean geometry. Variations of this
>axiom (that there is no such line, or infinitely many) also lead
>to interesting mathematical theories (hyperbolic and elliptic geometries).
>And in turns out that non-euclidean geometries indeed describe reality,
>if one doesn't look at space alone, but at spacetime (and always includes
>both a direction in space and a direction in time). Even though only
>the original axioms seems "self-evident", and not the others.

I think you mean "does not intersect" rather than "is not identical",
that is, I think you are citing the axiom that there is only one line,
parallel to a given line, through a given point not on that given
line.

Other than that, it sounds fine to me.
--
"I begin to envy Petronius."
"I have envied him long since."
.

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