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Topic: Re: It is a very bad idea and nothing less than stupid to define 1/3
= 0.333...

Replies: 42   Last Post: Oct 9, 2017 11:53 AM

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 netzweltler Posts: 472 From: Germany Registered: 8/6/10
Re: It is a very bad idea and nothing less than stupid to define 1/3
= 0.333...

Posted: Oct 4, 2017 4:19 AM

Am Mittwoch, 4. Oktober 2017 01:29:50 UTC+2 schrieb Jim Burns:
> On 10/3/2017 3:25 PM, netzweltler wrote:
> > Am Dienstag, 3. Oktober 2017 16:20:25 UTC+2
> > schrieb Jim Burns:

> >> On 10/3/2017 3:21 AM, netzweltler wrote:
> >>> Am Dienstag, 3. Oktober 2017 03:22:11 UTC+2
> >>> schrieb Jim Burns:

> >>>> On 10/2/2017 2:47 PM, netzweltler wrote:
> >>>>> Am Montag, 2. Oktober 2017 20:35:56 UTC+2
> >>>>> schrieb Jim Burns:

> >>>>>> On 10/2/2017 1:58 PM, netzweltler wrote:
> >>>>>>> Am Montag, 2. Oktober 2017 17:59:21 UTC+2
> >>>>>>> schrieb Jim Burns:

> >>>>>>>> On 10/1/2017 3:22 AM, netzweltler wrote:
>
> >>>>>>>>> Do you agree that 0.999... means infinitely many
> >>>>>>>>> commands
> >>>>>>>>> Add 0.9 + 0.09
> >>>>>>>>> Add 0.99 + 0.009
> >>>>>>>>> Add 0.999 + 0.0009
> >>>>>>>>> ...?

> >>>>>>>>
> >>>>>>>> 0.999... does not mean infinitely many commands.

> >>>>>>>
> >>>>>>> But that's exactly what it means.

> >>>>>>
> >>>>>> That's not the standard meaning.

> >>>>>
> >>>>> So, you disagree that
> >>>>> 0.999... = 0.9 + 0.09 + 0.009 + ... ?

> >>>>
> >>>> Your '...' is not usable. If we say what we _really_ mean,
> >>>> in a manner clear enough to reason about, then the '...'
> >>>> disappears. Also, what we are left with are finitely many
> >>>> statements of finite length. You will not find infinitely
> >>>> many commands in those finitely-many, finite-length
> >>>> statements.

>
> [...]
>

> >>> Sorry, no. The meaning of "..." is absolutely clear in this
> >>> context and

> >>
> >> Is it clear to you? Really?
> >>
> >> I ask because the basis for your whole complaint, in many
> >> threads, is that '...' means "infinitely many commands" in
> >> some way but then you're all "Whoa! that makes no sense, guys".
> >> It does not look to me as though _what you think_ '...'
> >> means in this context is at all clear _to you_ .
> >>
> >> ( _What you think_ it means is not what it means. This is
> >> _my_ point.)

> >
> > Sorry, I don't get what you are trying to teach me.

>
> Do you understand our first exchange? I'm not asking if you
> _agree_ with me. Do you _understand_ me?
>
> <Burns<netzweltler>>
>

> > Do you agree that 0.999... means infinitely many
> > commands
> > Add 0.9 + 0.09
> > Add 0.99 + 0.009
> > Add 0.999 + 0.0009
> > ...?

>
> 0.999... does not mean infinitely many commands.
>
> </Burns<netzweltler>>

To me it looks like that we don't even agree, that there are infinitely many 9s following.
If there are infinitely many 9s following then there is a bijection between N and the decimal places in 0.999...
If there are infinitely many 9s following then we are dealing with an infinite stepwise process as described above and I can't see why this shouldn't mean "infinitely many commands".

Date Subject Author
10/2/17 Guest
10/2/17 netzweltler
10/2/17 Jim Burns
10/3/17 netzweltler
10/3/17 FromTheRafters
10/3/17 Jim Burns
10/3/17 FromTheRafters
10/3/17 Jim Burns
10/3/17 FromTheRafters
10/3/17 netzweltler
10/3/17 bursejan@gmail.com
10/4/17 netzweltler
10/3/17 FromTheRafters
10/3/17 Jim Burns
10/3/17 FromTheRafters
10/3/17 netzweltler
10/3/17 Jim Burns
10/4/17 netzweltler
10/4/17 Jim Burns
10/4/17 netzweltler
10/5/17 Jim Burns
10/5/17 netzweltler
10/5/17 Jim Burns
10/5/17 netzweltler
10/5/17 Jim Burns
10/5/17 netzweltler
10/5/17 Jim Burns
10/5/17 FromTheRafters
10/6/17 netzweltler
10/6/17 Jim Burns
10/7/17 FromTheRafters
10/8/17 FromTheRafters
10/8/17 netzweltler
10/8/17 Jim Burns
10/8/17 netzweltler
10/8/17 Jim Burns
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10/9/17 Jim Burns
10/9/17 netzweltler
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